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CAPLUS COPYRIGHT 2011 ACS
||Process for preparation of trans-asenapine employing stereoselective hydrogenation of a dibenzoxepine intermediate
||Zhu, Jie; Keltjens, Rolf; Firet, Judith Janneke
||Synthon B.V., Neth.
||PCT Int. Appl., 29pp. CODEN: PIXXD
Asenapine and related trans-isomer bicyclic compds. can be obtained by reducing a compound of Formula (C) to preferentially form a trans-isomer compound of Formula (D), followed by subsequent ring closure to form a compound of Formula (B) such as asenapine. A method for preparing asenapine (I), and related trans-isomer bicyclic compds., is disclosed. The stereoselectivity arises via the hydrogenation of a dibenzoxepine dicarboxylate intermediate II (R1 and R2 independently = alkyl, alkynyl or aralkyl group). The reduction product of II (R1 and R2 = Me) then undergoes heterocyclization with methylamine to provide the desired I.
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