Lewis acid - promoted cyclopropanation of α,β-unsaturated carbonyl compounds by diazocarbonyl compounds. A facile synthesis of 1,2-disubstituted cyclopropylcarbonyl compounds of high isomeric purity

✍ Scribed by Michael P. Doyle; William E. Buhro; Joseph F. Dellaria Jr.

• Book ID: 104237957
• Publisher: Elsevier Science
• Year: 1979
• Tongue: French
• Weight: 293 KB
• Volume: 20
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)86609-0

✦ Synopsis

Antimony pentafluoride

promotes condensation of a,&unsaturated aldehydes ad ketones with diuzocarbony2 compowzds to form I,%disubstituted cycZopropyZcarbony2 compounds in preparativeZy useful yields.

Isomerization of the cycZopropyba.rbonyt derivative by antimony pentaf'luoride produces the more stable geometrica isomer in high isomer+ purity.

Diazo compounds react with a wide variety of unsaturated substrates to form cyclopropane derivatives under thermal and photochemical conditions or in the presence of transition metal catalysts.