Is a hydrogen-bonded carbene an intermediate in the organoaluminum-induced ring opening of pyranosides? ring opening of pyranosides?

✍ Scribed by Roger Olsson; Ulf Berg; Torbjörn Frejd

• Publisher: Elsevier Science
• Year: 1997
• Tongue: French
• Weight: 198 KB
• Volume: 38
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(97)01250-1

✦ Synopsis

Semiempirical and ab initio quantum chemical computations indicate that the intermediate formed prior to the selectivity-determining methyl transfer step in the reaction between glycosides and trimethylaluminum is a strongly hydrogen-bonded equilibrium O'--H-C ---O-H'"C, which is proposed to be an important selectivity promoting factor in the alkyl transfer reaction.