Chirality Breeding via Asymmetric Phosphination. Palladium-Catalyzed Diastereoselective Synthesis of a P-Stereogenic Phosphine

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• 作者：Natalia F. Blank ; Katherine C. McBroom ; David S. Glueck ; W. Scott Kassel ; and Arnold L. Rheingold
• 刊名：Organometallics
• 出版年：2006
• 出版时间：March 27, 2006
• 年：2006
• 卷：25
• 期：7
• 页码：1742 - 1748
• 全文大小：125K
• 年卷期：v.25,no.7(March 27, 2006)
• ISSN：1520-6041

文摘

Methylation of the crystallographically characterized primary alkylphosphine-borane PH₂Men(BH₃)(3, Men = (-)-menthyl) under phase-transfer conditions, followed by deprotection, gave the secondaryphosphine PH(Me)(Men) (2). Cross-coupling of 2 with PhI in the presence of NaOSiMe₃ selectivelygave S_P-PPh(Me)(Men) (1, L) with a variety of Pd catalyst precursors, including a complex of diastereopureS_P-1, trans-PdL₂(Ph)(I) (6a). In this reaction, the chiral phosphine L formally acted as a ligand in catalysisof its selective self-reproduction, but 6a was partially transformed to its diastereomers, trans-Pd(S_P-1)(R_P-1)(Ph)(I) (6b) and trans-Pd(R_P-1)₂(Ph)(I) (6c), and several other intermediates were observed duringcatalysis.