Exhibit 2.1

AMENDMENT NO. 2 TO AGREEMENT AND PLAN OF MERGER

This AMENDMENT NO. 2 to the AGREEMENT AND PLAN OF MERGER, dated as of June 25, 2026 (this “Amendment”), is made by and between Bleichroeder Acquisition Corp. II, a Cayman Islands exempted company (“Parent”), Bleichroeder Acquisition France Merger Sub 2, a société anonyme formed under the laws of the Republic of France (“Parent Merger Sub”), and Pasqal Holding SAS, a société par actions simplifiée formed under the laws of the Republic of France (the “Company”). Parent, Parent Merger Sub and the Company shall each be referred to herein from time to time individually as a “Party” and collectively as the “Parties”.

RECITALS:

WHEREAS, Parent, Parent Merger Sub and the Company are parties to that certain Agreement and Plan of Merger, dated as of February 28, 2026, as amended by Amendment No. 1 to the Agreement and Plan of Merger and Assignment and Assumption Agreement, dated as of May 26, 2026 (as may be further amended or supplemented from time to time, the “Business Combination Agreement”);

WHEREAS, pursuant to Section 11.6 of the Business Combination Agreement, the Business Combination Agreement may be amended or waived prior to the Effective Time if, but only if, such amendment or waiver is in writing and executed by the Parties; and

WHEREAS, the Parties desire to amend the Business Combination Agreement as hereinafter set forth.

NOW, THEREFORE for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereby agree as follows:

“Closing of the Merger. Unless this Agreement is earlier terminated in accordance with Article X, the closing of the Merger (the “Closing”) will take place (x) at least one Business Day after the date on which the later to occur of the required approval of the shareholders of Parent Merger Sub and the Requisite Company Vote has been obtained and (y) after the Reincorporation Merger Effective Time (the “Merger Approval Date”) by conference call and by exchange of signature pages via email or other electronic transmission, as permitted under applicable Laws, or at such other place and time as the Company and the Parent Parties may mutually agree upon (the date on which the Closing actually occurs being hereinafter referred to as the “Closing Date”). The Parties may participate in the Closing via electronic means.

Upon and immediately following the Merger Effective Time, the Surviving Corporation’s board of directors’ internal regulations will include the list of restricted matters set forth in Exhibit H.”

“Equity Incentive Plan. Effective as of (and contingent on) the Closing, the Surviving Corporation will adopt a new equity incentive plan in a form and substance reasonably acceptable to Parent and the Company and which will be approved by the Surviving Corporation’s board of directors (the “LTIP”), and which LTIP will provide for awards for a number of Surviving Corporation Shares (in the form of founder’s warrants – BSPCEs – or free shares – actions gratuites - up to ten percent (10%) of the aggregate number of Surviving Corporation Shares issued and outstanding immediately after the Closing on a fully-diluted and as-converted basis (after giving effect to the Parent Shareholder Redemptions, if any) (the “LTIP Share Reserve”). Parent and the Company will negotiate further edits to the LTIP (including vesting criteria for new award recipients based on performance conditions) in good faith based on recommendations from the Company’s compensation consultant, which will be incorporated into the LTIP, subject to the approval of the Surviving Corporation’s board of directors, in advance of the Parent Extraordinary General Meeting.”

[Signature pages follow]

IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be executed by their respective authorized representatives as of the date first written above.