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                                                                EXHIBIT 5.5




                          DEBENTURE PURCHASE AGREEMENT

          DEBENTURE PURCHASE AGREEMENT dated July 26, 1996, between MCN
Corporation, a Michigan corporation (the "Issuer"), and MCN Financing I, a
statutory business trust formed under the laws of the State of Delaware (the
"Trust").

          WHEREAS the Trust desires to purchase from the Issuer, and the Issuer
desires to sell to the Trust, certain of the Issuer's securities. 

          NOW, THEREFORE, the parties hereto agree as follows: 

          1.  The Trust hereby offers to purchase and the Issuer hereby accepts
such offer and agrees to issue and sell to the Trust the entire $82,474,250
aggregate principal amount of the Issuer's 8 5/8% Junior Subordinated Debentures
(the "Debentures") issued pursuant to an indenture dated as of September, 1994,
between the Issuer and NBD Bank (as supplemented by a First Supplemental
Indenture, dated April 17, 1996, as so supplemented, the "Base Indenture"), as
Indenture Trustee, as supplemented by a Second Supplemental Indenture, dated as
of July 24, 1996 (the Base Indenture, as so supplemented, is hereinafter
referred to as the "Indenture") in consideration of
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the payment to it on or before the date hereof of $82,474,250.

          2.  The Issuer represents and warrants that the Debentures have been
duly authorized and executed by the Issuer, and when duly authenticated and
delivered to the Trust, will constitute the legal, valid and binding obligations
of the Issuer entitled to the benefits of the Indenture and enforceable against
the Issuer in accordance with their terms (subject to applicable bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and other similar
laws affecting creditors' rights generally from time to time in effect, and
subject, as to en- forceability, to general principles of equity, regardless of
whether such enforceability is considered in a proceeding in equity or at law).







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          IN WITNESS WHEREOF, the parties hereto have caused this Debenture
Purchase Agreement to be duly executed as of the date hereof.



                                                    MCN CORPORATION



                                                    By: /s/ Sebastian Coppola
                                                       ------------------------
                                                    Name:   Sebastian Coppola
                                                    Title:  Vice President and
                                                            Treasurer


                                                    MCN FINANCING I


                                                    By: /s/ Daniel L. Schiffer
                                                       ------------------------
                                                    Name:   Daniel L. Schiffer
                                                    Title:  Regular Trustee