AMENDMENT NO. 1 TO THE AGREEMENT AND PLAN OF MERGER

Exhibit 2.1

AMENDMENT NO. 1

TO THE

AGREEMENT AND PLAN OF MERGER

This AMENDMENT NO. 1 (this “Amendment”), dated as of December 18, 2011, to the Agreement and Plan of Merger, dated as of September 6, 2011 (the “Merger Agreement”), is by and among International Paper Company, a New York corporation (“Parent”), Metal Acquisition Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Purchaser”), and Temple-Inland Inc., a Delaware corporation (the “Company”).

WHEREAS, Section 9.1 of the Merger Agreement provides for the amendment of the Merger Agreement in accordance with the terms set forth therein; and

WHEREAS, the parties hereto desire to amend the Merger Agreement as set forth below.

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and agreements set forth herein and for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, and intending to be legally bound hereby, the parties hereto do hereby agree as follows:

ARTICLE I

DEFINITIONS

Section 1.1 Definitions; References. Unless otherwise specifically defined herein, each term used herein shall have the meaning assigned to such term in the Merger Agreement. Each reference to “herein,” “hereunder,” “hereby” and “this Agreement” shall, from and after the date hereof, refer to the Merger Agreement as amended by this Amendment.

ARTICLE II

AMENDMENTS TO MERGER AGREEMENT

Section 2.1 Section 8.1(c). Section 8.1(c) of the Merger Agreement is hereby amended by deleting the words “the date that is nine months after the date hereof” and replacing them with “June 28, 2012”.

ARTICLE III

MISCELLANEOUS

Section 3.1 No Further Amendment. Except as expressly amended hereby, the Merger Agreement is in all respects ratified and confirmed and all the terms, conditions, and provisions thereof shall remain in full force and effect. This Amendment is limited precisely as written and shall not be deemed to be an amendment to any other term or condition of the Merger Agreement or any of the documents referred to therein.

Section 3.2 Effect of Amendment. This Amendment shall form a part of the Merger Agreement for all purposes, and each party thereto and hereto shall be bound hereby. From and after the execution of this Amendment by the parties hereto, any reference to the Merger Agreement shall be deemed a reference to the Merger Agreement as amended hereby.

Section 3.3 Governing Law. The parties hereto expressly agree that all the terms and conditions hereof shall be governed by and construed and enforced in accordance with, the laws of the State of Delaware applicable to agreements made and to be performed entirely therein.

Section 3.4 Separability Clause. In case any one or more of the provisions contained in this Amendment should be invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein shall not in any way be affected, impaired, prejudiced or disturbed thereby.

Section 3.5 Counterparts. This Amendment may be simultaneously executed in several counterparts, and all such counterparts executed and delivered, each as an original, shall constitute one and the same instrument.

Section 3.6 Headings. The descriptive headings of the several Articles of this Amendment were formulated, used and inserted in this Amendment for convenience only and shall not be deemed to affect the meaning or construction of any of the provisions hereof.

[Signature Page Follows]

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IN WITNESS WHEREOF, this Amendment has been duly executed and delivered by each party hereto as of the date first above written.

Signature Page to Amendment No. 1 to Merger Agreement