Two-Stage Synthesis of 3-(Perfluoroalkyl)-Substituted Vinyldiazocarbonyl Compounds and Their Nonfluorinated Counterparts: A Comparative Study

• Published in: Synthesis (Stuttgart) 2013-05, Vol.45 (9), p.1215-1226
• Main Authors: Supurgibekov, Murat B., Prakash, G. K. Surya, Nikolaev, Valerij A.
• Format: Article
• Language: English
• ISSN: 0039-7881; 1437-210X
• DOI: 10.1055/s-0032-1318309

Abstract Two approaches for the synthesis of fluorinated ( F ) and nonfluorinated ( H ) 4-(alkoxycarbonyl)-substituted cis - and trans -vinyldiazocarbonyl compounds with substituents of variable stereoelectronic nature (H, Me, Ph, CF 3 , OTBS) at the C-3 atom of the vinyl double bond from the relevant 1,3-dicarbonyl compounds were compared: a pathway using the Wittig reaction followed by a diazo transfer reaction was most efficient for the synthesis of the H -vinyldiazocarbonyl compounds (total yields of up to 60%), while the yields of their F -analogues under similar conditions did not exceed 16–37%. An approach via diazo transfer followed by the Wittig reaction, in contrast, is more effective for the preparation of F -vinyldiazocarbonyl compounds (total yields 37–69%). The configuration of the resulting F - and H -vinyldiazocarbonyl compounds is evidently controlled by the steric bulk of the substituent at the C-3 atom of the vinyl double bond and, in addition, depends on the specific synthetic pathway.