ChemInform Abstract: NEUE SYNTHESE VON CYCLOPROPANOLEN

The Chemistry of Cyclopropanols

“…Cyclopropanation of enol derivatives, especially that of trialkylsilyl enol ethers, by carbene or carbenoid reagents is the most widely used method for the preparation of O-substituted cyclopropanols [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] and has been reviewed extensively. 20,24,[26][27][28][30][31][32][33] In the past two decades, this approach has also been extended to the preparation of cyclopropanols.…”

“…Cyclopropanation of enol derivatives, especially that of trialkylsilyl enol ethers, by carbene or carbenoid reagents is the most widely used method for the preparation of O-substituted cyclopropanols − and has been reviewed extensively. ,,− ,− In the past two decades, this approach has also been extended to the preparation of cyclopropanols. Cyclopropanation of carboxylic acid derivatives with reagents which supply two carbon atoms for the formation of a cyclopropane ring has also been developed as an effective alternative approach to cyclopropanols.…”

“…Cyclopropanation of metal enolates with zinc or samarium carbenoids constitutes a direct route to cyclopropanols. ,− Imamoto and co-workers found that deprotonation of ketones with strong bases and treatment of the generated enolates with CH 2 I 2 −SmI 2 or CH 2 I 2 −Sm led to 1-substituted cyclopropanols in good yields . The cyclopropanation of enolates using these reagents proceeded in a highly regioselective manner; thus, for example, propiophenone treated with lithium diisopropylamide (LDA), and then with CH 2 I 2 −SmI 2 , gave cis -2-methyl-1-phenylcyclopropanol ( 1) in moderate yield (Scheme ) …”