An Enantioselective Chemoenzymatic Synthesis of the Four 1-Amino 2-Methylcyclopropane Carboxylic Acids

Stereoselective Cyclopropanation Reactions

“…Many processes were reported in the 1980s and early 1990s for the desymmetrization of diester cyclopropanes such as 494 . The enantiomeric excess ranges from 20 to 100%, depending on the substituents and the esterase source (Scheme ) 41 Enzymatic Desymmetrization of Meso Diesters …”

Natural Occurrence, Syntheses, and Applications of Cyclopropyl-Group-Containing α-Amino Acids. 1. 1-Aminocyclopropanecarboxylic Acid and Other 2,3-Methanoamino Acids

“…Thus, dimethyl 2-methylcyclopropane-1,1-dicarboxylate ( 300 ) was subjected to the action of two enzymes, pig liver esterase (PLE) and an esterase (E 30.000) from bacterial origin, and depending on the order of steps, all four stereoisomers of norcoronamic acid 139 were obtained …”

Rh(II)-Catalyzed Enantioselective Cyclopropanation of Olefins with Dimethyl Malonate via in Situ Generated Phenyliodonium Ylide

“…Thus, 3a has been used as an intermediate in the enantioselective synthesis of sertraline 14b. In addition, the selective hydrolysis of the trans -ester function opens access to a variety of 1,1-difunctionalized cyclopropanes, such 1-aminocyclopropane carboxylic acids . The present procedure is complementary to the enantioselective cyclopropanation with silanyloxyvinyl diacoacetates, which allows for diastereo- and enantioselective introduction of two different carbonyl functions …”