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An Asymmetric Organocatalytic Quadruple Cascade to Tetraaryl-Substituted 2-Azabicyclo[3.3.0]octadienones.

ABSTRACT: A new asymmetric organocatalytic three-component quadruple cascade of ?-ketoamides with ?,?-unsaturated aldehydes is described. The reaction is catalyzed by the (S)-diphenylprolinol TMS ether catalyst and proceeds via an aza-Michael/aldol condensation/vinylogous Michael/aldol condensation sequence to yield tetraaryl-substituted 2-azabicyclo[3.3.0]octadienone derivatives. The cascade products are obtained with good to very good yields (34-71%), virtually complete diastereoselectivities (>20:1), and very good enantioselectivities (84-97%).

SUBMITTER: Joie C

PROVIDER: S-EPMC4178286 | biostudies-other | 2014 Jun

REPOSITORIES: biostudies-other

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An Asymmetric Organocatalytic Quadruple Cascade to Tetraaryl-Substituted 2-Azabicyclo[3.3.0]octadienones.

Joie Céline C Deckers Kristina K Raabe Gerhard G Enders Dieter D

Synthesis 20140601 11

A new asymmetric organocatalytic three-component quadruple cascade of α-ketoamides with α,β-unsaturated aldehydes is described. The reaction is catalyzed by the (<i>S</i>)-diphenylprolinol TMS ether catalyst and proceeds via an aza-Michael/aldol condensation/vinylogous Michael/aldol condensation sequence to yield tetraaryl-substituted 2-azabicyclo[3.3.0]octadienone derivatives. The cascade products are obtained with good to very good yields (34-71%), virtually complete diastereoselectivities (>2 ...[more]

PMID: 25278633

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