Lloyd-Jones, Guy C. published the artcileEnantioselective homoallyl-cyclopropanation of dibenzylideneacetone by modified allylindium halide reagents-rapid access to enantioenriched 1-styryl-norcarene, Recommanded Product: (S)-Methyl 2-(2-chlorophenyl)-2-hydroxyacetate, the main research area is asym synthesis styryl norcarene homoallyl cyclopropanation ring closing metathesis; enantioselective cyclopropanation allylindium halide dibenzylideneacetone modifier.
Dibenzylideneacetone reacts with in situ-generated allylindium halide reagents to yield 2-(3”-butenyl)-1,1-bis[(E)-2′-phenylethenyl]cyclopropane I via a homoallyl-cyclopropanation reaction. A range of enantiomerically enriched ligands have been tested as stoichiometric asym. modifiers for this process. Enantiopure compounds such as cinchona alkaloids, ephedra, aminoalcs. and tartaric acid derivatives, which have proven of utility as asym. modifiers for the indium-mediated allylation of aldehydes and ketones, were very inefficient in the homoallyl-cyclopropanation. However, mandelic acid derivatives, in particular mandelates, were found to be of significant potential. The absolute stereochem. of the cyclopropane I has been determined by degradation to 1,1-dicarboxymethyl-2-butylcyclopropane, converging with an independent enantioselective synthesis starting from hexene. Under optimized conditions by using allylindium iodide reagents and working-up with aqueous Na2SO3 to avoid iodine-mediated polymerization, I can be generated in 86% yield and 94/6 er enantiopurity with (S)-Me mandelate as modifier. The cyclopropane product I undergoes RCM to afford 1-styrylnorcarene II without loss of enantiopurity.
Tetrahedron published new progress about Cyclopropanation catalysts. 32345-60-1 belongs to class chlorides-buliding-blocks, name is (S)-Methyl 2-(2-chlorophenyl)-2-hydroxyacetate, and the molecular formula is C9H9ClO3, Recommanded Product: (S)-Methyl 2-(2-chlorophenyl)-2-hydroxyacetate.
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics