SUPPLEMENTAL AGREEMENT

                                 AMENDMENT NO. 1

                                       TO

                             SUPPLEMENTAL AGREEMENT


          AMENDMENT NO. 1, dated as of February 13, 1996, between Rockefeller
Center Properties, Inc. ("RCPI") and Xxxxxxx Xxxxx Mortgage Company ("GSMC") to
the Supplemental Agreement, dated November 7, 1995 (the "Supplemental
Agreement"), between RCPI and GSMC.

          WHEREAS, RCPI, Whitehall Street Real Estate Limited Partnership V,
Rockprop, L.L.C., Xxxxx Xxxxxxxxxxx, Exor Group S.A., Troutlet Investments
Corporation, RCPI Holdings Inc. and RCPI Merger Inc., have entered into
Amendment No. 1 to the Agreement and Plan of Merger ("Amendment No. 1 to the
Merger Agreement"), dated as of February 12, 1996;

          WHEREAS, GSMC and RCPI desire to amend the Supplemental Agreement as
set forth herein to conform to the relevant provisions of the Merger Agreement,
as amended by Amendment No. 1 to the Merger Agreement.

          NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto hereby agree as follows:

          1.   Capitalized terms used herein but not otherwise defined herein
shall have the respective meanings ascribed thereto in the Supplemental
Agreement.  Unless otherwise indicated, all paragraph references are to numbered
paragraphs in the Supplemental Agreement.

          2.   Paragraph 1 shall be amended by adding the following language
immediately after the words "plus (B) $12 million to pay Permitted Expenses (as
defined in the Merger Agreement) if the Closing Date (as defined in the Merger
Agreement) shall not have occurred on or before December 31, 1995":

          "plus (C) $2.5 million to pay Permitted Expenses if the Closing Date
          shall not have occurred on or before March 31, 1996".


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          3.   Paragraph 2 shall be amended by replacing the word "and"
immediately prior to clause (b) with a "," and adding the following language at
the end of the sentence:

          "and (c) of the $2.5 million described in clause (C) of paragraph 1
          above, an amount sufficient to pay all interest that will become due
          from RCPI to Whitehall and GSMC on or before April 30, 1996 shall be
          available only to pay such interest".

          4.   Paragraph 3 shall be amended by replacing the words "March 31,
1996" in the proviso with the words "April 30, 1996".

          5.   Except as amended hereby, all of the terms and conditions of the
Supplemental Agreement shall in all respects continue in full force and effect.



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          6.   This Amendment No. 1 to the Supplemental Agreement may be
executed in one or more counterparts, each of which shall be an original and all
of which, when taken together, shall constitute one and the same instrument.

          IN WITNESS WHEREOF, each of the parties has signed or caused this
Amendment No. 1 to the Supplemental Agreement to be signed as of the date first
written above.

                    ROCKEFELLER CENTER PROPERTIES, INC.


                    By:  /s/ Xxxxxxx X. Xxxxxxxx
                         -------------------------------
                         Xxxxxxx X. Xxxxxxxx
                         President and Chief
                         Executive Officer


                    XXXXXXX XXXXX MORTGAGE COMPANY

                    By:  Xxxxxxx Sachs Real Estate Funding Corp., General
                         Partner


                         By:  /s/ Xxxxxx X. Xxxxxxx
                              ---------------------------
                              Xxxxxx X. Xxxxxxx
                              President


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