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                                                                     EXHIBIT 5.1

                                November 8, 2000

Pinnacle Financial Partners, Inc.
The Commerce Center
211 Commerce Street, Suite 300
Nashville, Tennessee 37201

        Re:   Registration Statement on Form S-8
              Pinnacle Financial Partners, Inc. 401(k) Plan

Ladies and Gentlemen:

        We have served as counsel for Pinnacle Financial Partners, Inc., a
Tennessee corporation (the "Company"), in connection with the registration of
400,000 shares of the Company's common stock, $1.00 par value (the "Shares"),
under the Securities Act of 1933, as amended, pursuant to a Registration
Statement on Form S-8 (the "Registration Statement"), which Shares are to be
issued and sold by the Company pursuant to the Pinnacle Financial Partners, Inc.
401(k) Plan (the "Plan").

        We have examined and are familiar with originals or copies (certified,
photostatic or otherwise identified to our satisfaction) of such documents,
corporate records and other instruments relating to the incorporation of the
Company and the authorization of the issuance of the Shares pursuant to the Plan
as we have deemed necessary and advisable. In such examinations, we have assumed
the genuineness of all signatures on all originals and copies of documents we
have examined the authenticity of all documents submitted to us as originals and
the conformity to original documents of all certified, conformed or photostatic
copies. As to questions of fact material and relevant to our opinion, we have
relied upon certificates or representations of Company officials and of
appropriate governmental officials.

        We express no opinion as to matters under or involving the laws of any
jurisdiction other than the corporate law of the State of Tennessee.

        Based upon and subject to the foregoing and having regard for such legal
considerations as we have deemed relevant, it is our opinion that:

        1.       The Shares have been duly authorized; and



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        2.       Upon the issuance and delivery of the Shares and the receipt of
                 payment therefor as provided in the Plan and as contemplated by
                 the Registration Statement, such Shares will be validly issued,
                 fully paid and non-assessable.

        We hereby consent to the filing of this opinion as Exhibit 5.1 to the
Registration Statement.

                                                  Very truly yours,

                                   /S/  POWELL, GOLDSTEIN, FRAZER & MURPHY LLP