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Highly enantioselective Mannich reactions with ?-aryl silyl ketene acetals and imines.

ABSTRACT: Mannich reactions with chiral silicon Lewis acid activated acylhydrazones and ?-aryl silyl ketene acetals and ?-aryl,?-alkyl silyl ketene imines proceed efficiently and with good to excellent levels of both diastereoselectivity and enantioselectivity. The reactions provide access to ?-aryl,?-hydrazido esters and ?-aryl,?-alkyl,?-hydrazido nitriles, which are valuable analogs of ?-amino acids.

SUBMITTER: Notte GT

PROVIDER: S-EPMC3042282 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Highly enantioselective Mannich reactions with α-aryl silyl ketene acetals and imines.

Notte Gregory T GT Baxter Vu Jenny M JM Leighton James L JL

Organic letters 20110114 4

Mannich reactions with chiral silicon Lewis acid activated acylhydrazones and α-aryl silyl ketene acetals and α-aryl,α-alkyl silyl ketene imines proceed efficiently and with good to excellent levels of both diastereoselectivity and enantioselectivity. The reactions provide access to α-aryl,β-hydrazido esters and α-aryl,α-alkyl,β-hydrazido nitriles, which are valuable analogs of β-amino acids. ...[more]

PMID: 21235253

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