Catalytic Enantioselective Synthesis of Functionalized Cyclopropanes from α-Substituted Allyl Sulfones with Donor-Acceptor or Diacceptor Diazo Reagents

The catalytic asymmetric synthesis of highly functionalized cyclopropanes from alpha-substituted allyl sulfones and silanes is reported. The reaction, using alpha-aryl diazoacetates or diacceptor diazo reagents, catalyzed by a chiral rhodium complex (Rh-2((S)-BTPCP)(4)), furnished the corresponding cyclopropanes in moderate to high yields (27-97 %), high diastereoselectivities (68 : 32 to 20 : 1 d.r.) and moderate to excellent ee (40-99 %). This methodology offers a privileged access to an underexplored class of enantioenriched cyclopropanes with a high level of functionality, an asset for further post-functionalization and their incorporation into more complex structure.

Automated summary

The catalytic asymmetric synthesis of highly functionalized cyclopropanes from alpha-substituted allyl sulfones and silanes is reported. The reaction, catalyzed by a chiral rhodium complex (Rh-2((S)-BTPCP)(4)) using alpha-aryl diazoacetates or diacceptor diazo reagents, provides moderate to high yields (27-97 %), high diastereoselectivities (68 : 32 to 20 : 1 d.r.) and moderate to excellent ee (40-99 %). This methodology offers an efficient route to enantioenriched cyclopropanes with a high level of functionality, which can be further modified and incorporated into more complex structures.