(2) STOCK PURCHASE AGREEMENT

EXHIBIT 99.2

C O N F I D E N T I A L

TRANSACTION DOCUMENT

(Stock Purchase)

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STOCK PURCHASE AGREEMENT

AMONG

BOK FINANCIAL CORPORATION,

BALTZ FAMILY PARTNERS, LTD.,

UNITED BANKS OF COLORADO, INC.

AND

FIRST UNITED BANK, N.A.,

Agreement Date of May 23, 2007

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TABLE OF CONTENTS

Page

1. Purpose of this Stock Purchase Agreement........................1

2. Purchase of UBC Common Stock....................................1

3. Purchase Price..................................................3

4. Representations and Warranties of BFP, UBC and Bank.............4

5. Representations and Warranties of BOKF..........................8

6. Covenants.......................................................9

7. Conditions Precedent to Closing by BOKF........................15

8. Conditions Precedent to Closing by UBC and Bank................16

9. Closing........................................................16

10. The General Escrow.............................................18

11. Loan Escrow....................................................19

12. Break-Up Fee...................................................20

13. Miscellaneous Provisions.......................................20

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STOCK PURCHASE AGREEMENT

This Stock Purchase Agreement ("Stock Purchase Agreement" or

"Agreement") is made as of May 23, 2007 (the "Agreement Date") among the

following parties (the "Parties"):

(i) BOK Financial Corporation, an Oklahoma corporation, ("BOKF");

(ii) Baltz Family Partners, Ltd, a Colorado limited partnership ("BFP");

(iii) First United Bank, NA ("Bank"); and,

(iv) United Banks of Colorado, Inc., a Colorado corporation ("UBC").

In consideration of the mutual covenants contained herein, the adequacy

of which is hereby expressly acknowledged, and intending to be legally bound

hereby, the Parties hereby agree as follows:

1. Purpose of this Stock Purchase Agreement. The purpose of this Stock Purchase

Agreement is as follows:

1.1. UBC is a bank holding company organized under the laws of Colorado with

offices in Englewood, Colorado. UBC is subject to regulation by the Board of

Governors of the Federal Reserve System ("FRB"). UBC owns all of the issued and

outstanding capital stock of Bank (headquartered in Englewood, Colorado). The

authorized capital stock of UBC consists solely of a single class of 50,000

shares of common stock of a par value of $5.00 per share of which 26,000 shares

are issued and outstanding at the Agreement Date (the "UBC Common Stock").

1.2. Bank is a national bank organized in accordance with the laws of the United

States of America. The authorized capital stock of Bank consists solely of a

single class of 250,000 shares of common stock of a par value of $10.00 per

share of which 250,000 shares are issued and outstanding at the Agreement Date

("Bank Common Stock").

1.3. BFP is a Colorado limited partnership and the sole shareholder of UBC. BFP

has four (4) limited partners as follows: Martha J. Baltz, Stephen P. Baltz,

Kimberly A. Baltz and Jennifer L. Baltz. Stephen P. Baltz and Martha J. Baltz

are the general partners of BFP. There are no other BFP Partners. For purposes

of this Agreement, "BFP Partners" means Martha J. Baltz, Stephen P. Baltz,

Kimberly A. Baltz and Jennifer L. Baltz.

1.4. BOKF is a financial holding company organized under the laws of the State

of Oklahoma. BOKF is subject to regulation by the FRB.

1.5. The purpose of this Stock Purchase Agreement is to set forth the terms and

conditions on which BOKF shall purchase all the Bank Common Stock from UBC.

2. Purchase of UBC Common Stock. Subject to the terms and conditions set forth

herein, at the Closing (as herein after defined), BFP shall sell, convey,

transfer, and deliver to BOKF certificates representing the UBC Common Stock,

and BOKF shall purchase from BFP all the

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UBC Common Stock in consideration of the purchase price set forth in this

Agreement (the "Transaction").

3. Purchase Price.

3.1. As total consideration for the purchase and sale of the UBC Common Stock

pursuant to this Agreement, BOKF shall pay to BFP the following (the

"Transaction Consideration"):

3.1.1. At Closing, an amount of United States Dollars equal to the Cash

Consideration (as hereafter defined) less the Escrow Amounts (as hereafter

defined) (the "Closing Amount"); and,

3.1.2. Upon termination of the Escrow Account, the remaining Escrow Amounts, if

any, as provided in Sections 10 and 11 herein.

3.2. The Cash Consideration shall equal (i) Forty Three Million Dollars

($43,000,000) less (ii) the Transaction Costs (as hereafter defined) and (iii)

the "Home Sale Loss" (as hereinafter defined).

3.3. For purposes of this Stock Purchase Agreement, "Transaction Costs" means:

(i) investment banking fees in excess of $250,000 that are payable to Carson

Medlin Company upon consummation of the Transaction; (ii) legal fees paid (or

payable) to Bracewell & Giuliani LLP in excess of $50,000 that have been

incurred in connection with the negotiation of this Agreement and the

consummation of the Transaction; and (iii) change in control payments in excess

of $25,000 that are payable to the Bank's officers and directors as a result of

the consummation of the Transaction.

3.4. For purposes of this Stock Purchase Agreement, the "Escrow Amounts" shall

be:

3.4.1. One Million Five Hundred Dollars ($1,500,000) to be deposited in the

General Escrow established in accordance with Section 10 (the "General Escrow");

and

3.4.2. Eight Million Dollars ($8,000,000) to be deposited in the Loan Escrow

established in accordance with Section 11 (the "Loan Escrow").

4. Representations and Warranties of BFP, UBC and Bank. BFP, UBC and Bank hereby

jointly and severally represent and warrant to BOKF that, now and at the time of

Closing:

4.1. Incorporation and Corporate Power. UBC is a corporation duly organized,

validly existing and in good standing under the laws of the State of Colorado.

Except as set forth on Schedule 4.1, Bank is a national bank duly organized,

validly existing and in good standing under the laws of the United States. BFP

is a limited partnership, organized, validly existing and in good standing under

the laws of the State of Colorado. Except as set forth on Schedule 4.1, Bank has

all the corporate power and authority necessary and required to own its

properties and to conduct its business as such business is now being conducted.

Except as set forth on Schedule 4.1, each of UBC and Bank (A) is in material

compliance with all applicable provisions of all applicable federal, state and

local statutes, laws, regulations, ordinances and other requirements

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of any governmental authorities (including, but not limited to, whether similar

or dissimilar, the Bank Holding Company Act of 1956, the Colorado Business

Corporation Act, Title 12 of the Code of Federal Regulations (the "Federal

Banking Code") and the filing of all administrative reports and the payment of

all material fees) in effect as of the date of this Stock Purchase Agreement,

and (B) shall be in material compliance therewith at the time of Closing.

4.2. Capital. The BFP Partners are the sole partners of BFP. BFP is the sole

shareholder of UBC. UBC owns all of the issued and outstanding Bank Common

Stock. The Bank Common Stock is and at the Closing will be all of the issued and

outstanding capital stock of Bank and will be owned by UBC.

4.3. Capitalization of Bank. The Bank Common Stock is validly issued and

outstanding, fully paid and (except as set forth in 12 U.S.C. ss. 55)

non-assessable.

4.3.1. There are no outstanding subscriptions, conversion privileges, calls,

warrants, options or agreements obligating the Bank to issue, sell or dispose

of, or to purchase, redeem or otherwise acquire any shares of their capital

stock (collectively, "options and rights"). At the Closing, there will be no

outstanding options or rights.

4.3.2. None of the Bank Common Stock has been issued or disposed of, or will as

of the Closing have been issued or disposed of, in violation of any preemptive

rights of any shareholder nor in violation of any agreement to which UBC or Bank

was or is a party. Bank has no subsidiaries and does not own, nor have the right

or obligation to acquire, any equity securities of any corporation, limited

liability company, partnership or other legal entity.

4.3.3. UBC is the lawful owner of the Bank Common Stock, free and clear of all

security interests, liens, encumbrances, equities and other charges.

4.4. Non-Violation of Other Agreements. The execution and delivery of this Stock

Purchase Agreement, and the compliance with its terms and provisions BFP, UBC

and Bank (including the execution and delivery of any document required to be

executed by BFP, UBC or Bank) will not breach any material agreement, lease, or

obligation, whether similar or dissimilar, by which BFP, UBC or Bank is bound.

4.5. Financial Statements. UBC has delivered to BOKF, or will have delivered to

BOKF prior to the Closing as soon as future financial statements are available,

copies of the following ("Financial Statements"):

4.5.1. Financial Statements for UBC (Unaudited) as of and for the periods

ending December 31, 2005 and 2006;

4.5.2. Reports of Condition and Income as filed with the Federal Deposit

Insurance Corporation for Bank, as of and for the periods ending December 31,

2004, 2005, and 2006;

4.5.3. Financial Statements (Audited) Bank, as of and for the periods ending

December 31, 2006 and the most recent monthly financial statements available as

of the Closing; and,

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4.5.4. The most recent monthly financial statements as are available as of the

Closing.

The Financial Statements described in Sections 4.5.1 and 4.5.2, (a)

have been prepared or will have been prepared in accordance with generally

accepted accounting principles, consistently applied and (b) fairly reflect the

financial condition and results of operations for the indicated periods. The

Financial Statements described in Sections 4.5.3 (including footnotes) and 4.5.4

(not including footnotes), (a) have been prepared or will have been prepared in

accordance with generally accepted accounting principles, consistently applied

and (b) fairly reflect the financial condition and results of operations for the

indicated periods, subject to normal year-end adjustments.

4.6. Material Liabilities. UBC and Bank have no liabilities (including, but not

limited to, whether similar or dissimilar, liabilities or obligations for taxes,

whether due or to become due) in excess of $25,000 except:

4.6.1. Those fully reflected or reserved against, or otherwise disclosed, in the

Financial Statements; and

4.6.2. Those specifically disclosed in the Schedule 4.6 to this Stock Purchase

Agreement.

4.7. Conduct of Business Prior to Closing. Except as set forth in Schedule 4.7,

since December 31, 2006, (A) Bank and UBC have carried on their businesses only

in the ordinary and normal course in a reasonable fashion in accordance with

industry standard, and (B) have not:

4.7.1. Incurred any material liabilities, commitments or obligations, contingent

or otherwise, or disposed of any of its assets, (for the purpose of this Section

4.7.1, material means $25,000 or more);

4.7.2. Incurred any bank or other institutional debt, or entered into any

agreement for the borrowing of money, except borrowing of federal funds or

borrowing from the Federal Home Loan Bank by Bank consistent with past

practices;

4.7.3. Suffered any material adverse change in the financial condition, assets,

liabilities, business or property of Bank or UBC taken as a whole; and/or

4.7.4. Made any material change in the manner in which business is conducted

(including, without limitation, branch closings, and any material change in

products offered to customers).

4.7.5. From the date of this Agreement to the date of Closing, neither Bank nor

UBC will voluntarily take any of the actions described in the foregoing

provisions of this Section 4.7 without the prior consent of BOKF, which consent

shall not be unreasonably withheld, delayed or denied.

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4.8. Tax Returns/Reports.

4.8.1. Except as set forth on Schedule 4.8, Bank and UBC have duly filed all tax

reports and returns required to be filed by them and have duly paid all taxes

and other charges claimed to be due from them by federal, state and local taxing

authorities.

4.8.2. No waivers of the statute of limitation have been issued with respect to

unaudited years.

4.8.3. Neither Bank nor UBC have any knowledge of any facts which could

reasonably be expected to result in a material deficiency with respect to

unaudited tax returns which would result in a material adverse effect on Bank or

UBC taken as a whole.

4.9. Contracts and Commitments.

4.9.1. A list of all contracts and commitments, other than credit and lending,

deposit or borrowing transactions entered into in the ordinary course of

business by Bank or UBC which are material to the business, operations or

financial condition of Bank or UBC as of this date, is set forth on Schedule

4.9. For the purpose of Schedule 4.9 only, materiality shall mean those

contracts and commitments (including a series of related contracts or

commitments) for which payment or other consideration to be furnished by any

party is more than $25,000 a year or $100,000 over the remaining life of the

contract.

4.9.2. Bank and UBC have in all material respects performed and are performing

all contractual and other obligations required to be performed by them.

4.10. Litigation. Except as set forth in Schedule 4.10, there is not pending,

or, to the knowledge of BFP, UBC and Bank threatened, any claim, litigation,

proceeding, order of any court or governmental agency, or governmental

investigation or inquiry to which UBC or Bank is a party or which involves the

Bank's or UBC's business operations, any of its property or any property leased

by Bank which, individually or in the aggregate:

4.10.1. May reasonably result in any material adverse change in the financial

condition, business, assets, properties or operations of Bank or UBC; or,

4.10.2. May reasonably involve the expenditure of more than a total of $25,000

in legal fees or costs;

4.11. Brokerage Fees. Bank has not incurred, nor will it incur, directly or

indirectly, any liability for brokerage, finder's, financial advisor's or

agent's fees or commissions by virtue of any commitment made by any of them in

connection with this Stock Purchase Agreement or any transaction contemplated

hereby other than fees payable to Carson Medlin Company upon consummation of the

Transaction, which payment shall be deducted from the Transaction Consideration

to the extent it exceeds $250,000.

4.12. Required Corporate Action. The execution, delivery and consummation of

this Stock Purchase Agreement has been duly and validly authorized by the board

of directors of UBC and Bank and the BFP Partners, in accordance with the

requirements of federal banking

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law, the Colorado Business Corporations Act, the Colorado Limited Partnership

Associations Act and all other applicable law.

4.13. Authorized Execution. This Stock Purchase Agreement has been duly executed

and delivered by duly authorized officers of UBC and Bank and BFP. This Stock

Purchase Agreement constitutes the legal, valid and binding agreement and

obligation of BFP, UBC and Bank, enforceable against each of them in accordance

with its terms, except as may be limited by applicable bankruptcy, insolvency,

moratorium, receivership, and other similar laws affecting the rights of

creditors generally.

4.14. Title to Assets; Encumbrances. Bank and UBC have good and valid title

(with respect to real estate, good and valid title shall mean such title as may

be insured on standard title insurance forms with no exceptions materially and

adversely affecting the value or use of the fee real estate) to its assets, and

in each case subject to no mortgage, pledge, lien, security interest,

conditional sale agreement, or other encumbrance of any nature whether similar

or dissimilar, except:

4.14.1. Such encumbrances which are purchase money security interests entered

into in the ordinary course of business consistent with past practice reflected

on their books and records;

4.14.2. Lessor's interests in leased tangible real and personal property

reflected on its books and records;

4.14.3. Such encumbrances for taxes and assessments not yet due and payable;

4.14.4. Encumbrances as do not materially detract from the value or interfere

with the use or operation of the asset subject thereto; and,

4.14.5. Repossessed and foreclosed assets acquired in satisfaction of debt

previously contracted.

4.15. Employees. Except as set forth on Schedule 4.15, none of the employees of

Bank or UBC is employed under any employment contract (oral or written) or is

the beneficiary of any compensation plan (oral or written) or is entitled to any

payment from Bank or UBC by reason of this Stock Purchase Agreement or the

Transaction and there are no employment contracts, management contracts,

consulting agreements, union contracts, labor agreements, pension plans, profit

sharing plans or employee benefit plans to which Bank or UBC is a party or by

which either of them is bound.

4.16. Environmental Laws. Except as set forth on Schedule 4.16, the existence,

use and operation of the assets of Bank and UBC is in material compliance with

all applicable statutes, rules and regulations including, without limiting the

generality of the foregoing, all environmental and zoning laws and the Americans

With Disabilities Act.

4.17. Loan Portfolio. (A) All loans and discounts shown on the Financial

Statements were and will be made in all material respects for good, valuable and

adequate consideration in the ordinary course of Bank's business, in accordance

in all material respects with sound banking

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practices, and are not subject to any material known defenses, setoffs or

counterclaims, including without limitation any such as are afforded by usury or

truth in lending laws, except as may be provided by bankruptcy, insolvency or

similar laws or by general principles of equity; (B) the notes or other

evidences of indebtedness evidencing such loans and all forms of pledges,

mortgages and other collateral documents and security agreements are and will

be, in all material respects, enforceable, valid, true and genuine and what they

purport to be; and (C) Bank has complied and will prior to the Closing Date

comply with all laws and regulations relating to such loans (including, but not

limited to, obtaining property appraisals of a nature required by regulation),

or to the extent there has not been such compliance, such failure to comply will

not materially interfere with the collection of any such loan or require

additional action under applicable laws or regulations.

4.18. Zoning and Related Laws. All real property owned or leased by Bank or UBC

and the use thereof complies with all applicable laws, ordinances, regulations,

orders or requirements, including without limitation, building, zoning and other

laws, except as to any violations which would not have a material adverse affect

on the financial condition of Bank.

4.19. Compliance with Law. Except as set forth on Schedule 4.19, Bank and UBC

have all licenses, franchises, permits and other governmental authorizations

that are legally required to enable them to conduct their business as they are

currently doing so in all material respects and are in compliance with all

applicable laws and regulations. Without limiting the generality of the

foregoing, Bank has at all times maintained their employee benefit plans in

compliance with the Internal Revenue Code and the Employee Retirement Income

Security Act and all applicable rules and regulations promulgated pursuant

thereto. All data and reports respecting Bank employee benefit plans provided to

BOKF are complete and correct in all material respects. UBC has officers and

directors but no employees.

4.20. Agreements with Regulatory Agencies. Except as set forth on Schedule 4.20

and other than Stipulation and Consent to Issuance of Consent Order to the

Office of the Comptroller of the Currency dated October 5, 2006, neither Bank

nor UBC is subject to any cease-and-desist or other order issued by, or a party

to any written agreement or memorandum of understanding with or is a party to

any commitment letter or similar undertaking to, or is subject to any order or

directive, or is a recipient of any extraordinary supervisory letter from, or

has adopted any board resolutions at the request of (each a "Regulatory

Agreement") any regulatory agency that materially restricts the conduct of its

business or that in any manner relates to its capital adequacy, its credit

policies, its management or its business, nor has Bank or UBC been advised by

any regulatory agency that it is considering issuing or requesting any

Regulatory Agreement.

4.21. Actions From and After December 31, 2006. Except as set forth on Schedule

4.21, Bank has not taken any action from and after December 31, 2006 until the

date of this Agreement that is prohibited to be taken from and after the date of

this Agreement by the provisions of Section 6.3. Without limiting the generality

of the foregoing:

4.21.1. Bank has paid no dividends;

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4.21.2. From and after December 31, 2006, except as otherwise disclosed in the

Schedules to this Agreement, Bank has made no changes in the compensation of any

employees other than non-material cost of living and merit adjustments

consistent with past practices or as otherwise provided on Schedule 4.21.2.

4.22. Insurance. Bank and UBC have been continuously covered by those insurance

policies in the amounts, with the deductibles and for the periods identified on

Schedule 4.22 (the "Insurance Policies"). The Insurance Policies do not have any

exceptions or exclusions other than those typically found in policies of that

type.

4.23. Survival and Independence of Representations and Warranties. The

representations and warranties of BFP, UBC and Bank made in this Stock Purchase

Agreement shall survive the Closing notwithstanding any investigation or

knowledge of BOKF; provided BOKF shall give notice to the Agent (as herein after

defined) of any claim of a breach of any such representations and warranties on

or before the second anniversary of the Closing Date (the "Claim Notice

Deadline"). Each of the representations and warranties of UBC and Bank set forth

in this Stock Purchase Agreement is a separate and independent representation

and warranty, shall be cumulative of and in addition to all other warranties and

representations, and shall not limit or be interpreted to be in derogation of

any other representation or warranty made herein. Any disclosure made on any

Schedule hereto shall be applicable to the entire Agreement and not just one

representation or warranty.

4.24. Knowledge. As used herein, the knowledge of BFP, UBC and/or the Bank shall

mean the knowledge of any one or more of the following persons: the Chief

Executive Officer, Chief Financial Officer, Chief Lending Officer or Human

Resources Officer any member of the Board of Directors of UBC or the Bank have

or, in the reasonable exercise of their respective duties and responsibilities,

should have knowledge.

5. Representations and Warranties of BOKF. BOKF represents and warrants to BFP,

UBC and Bank that:

5.1. Incorporation and Corporate Power. BOKF is a corporation duly organized,

validly existing and in good standing under the laws of the state of Oklahoma.

BOKF has all the corporate power and authority necessary and required to

consummate the transactions contemplated by this Stock Purchase Agreement.

5.2. Non-Violation of Other Agreements. The execution and delivery of this Stock

Purchase Agreement, and compliance with its terms and provisions by BOKF and the

execution of any document required to be executed by BOKF, will not:

5.2.1. Violate, conflict with or result in the breach of their respective

certificates of incorporation or bylaws or any of the terms, conditions or

provisions of any agreement or instrument to which BOKF is a party, or by which

BOKF is bound;

5.2.2. Result in the creation or imposition of any lien, charge, encumbrance or

restriction of any nature whatever upon any of the property, contracts or

business of BOKF; or,

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5.2.3. Require the consent of any party to a contract with BOKF and in order to

keep the contract enforceable.

5.3. Required Corporate Action. The execution, delivery and consummation of this

Stock Purchase Agreement by BOKF has been duly and validly authorized by the

board of directors of BOKF. The approval of the shareholders of BOKF is not

required. This Stock Purchase Agreement has been duly executed and delivered by

duly authorized officers of BOKF. This Stock Purchase Agreement constitutes a

legal, valid and binding agreement and obligation of BOKF enforceable against

BOKF in accordance with its terms, except as may be limited by applicable

bankruptcy, insolvency, moratorium, receivership, and other similar laws

affecting the rights of creditors generally.

5.4. Brokerage Fees. BOKF has not incurred or will incur, directly or

indirectly, any liability for brokerage, finder's, financial advisor's or

agent's fees or commissions by virtue of any commitment made by BOKF in

connection with this Stock Purchase Agreement or any transaction contemplated

hereby. BOKF has no knowledge that any party has asserted any claim of such

nature against BOKF.

5.5. Survival and Independence of Representations and Warranties. The

representations and warranties of BOKF made in this Stock Purchase Agreement

shall not survive the Closing hereof. Each of the representations and warranties

of BOKF set forth in this Stock Purchase Agreement is a separate and independent

representation and warranty, shall be cumulative of and in addition to all other

warranties and representations; and shall not be interpreted to be in derogation

of any other representation or warranty or limit any other representation or

warranty made herein.

6. Covenants.

6.1. Full Access. In order that BOKF shall have the full opportunity to make

such investigations as it shall reasonably desire concerning Bank and UBC and

its business affairs, Bank and UBC shall:

6.1.1. Give BOKF, its employees, counsel, accountants and other authorized

representatives, as necessary to conduct the investigation, full access, upon

reasonable notice to Bank and UBC and at reasonable times without unduly

interfering with the conduct of business by Bank and UBC throughout the period

up to the Closing, to all of the facilities, properties, books, contracts and

records of Bank and UBC, including access to all meetings of the Bank's and

UBC's Board of Directors, committees or officers (except for the portions of

such meetings where this Agreement is discussed and where the presence of BOKF

representatives could operate as a waiver of the Bank's or UBC's attorney-client

privilege).

6.1.2. Authorize its accountants to give BOKF full access to the accountants'

records, including work papers; and,

6.1.3. Furnish to BOKF throughout the period up to the Closing all additional

financial, operating and other information concerning Bank and UBC and their

business affairs, as BOKF may reasonably request.

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6.1.4. Notify BOKF's representative, Stacy Kymes, within one business day of any

material changes, issues or claims which arise between the Effective Date of

this Agreement and Closing.

All information provided pursuant to this Section 6.1 shall be subject

to the provisions of Section 6.5.

6.2. Conduct of Business Prior to the Closing Date. From this date until the

Closing Date, Bank and UBC shall, except as may be first approved in writing by

BOKF (such approval not to be unreasonably withheld, delayed or denied) or as is

otherwise permitted or conte