Room temperature intramolecular hydro-O-alkylation of aldehydes: sp3 C-H functionalization via a Lewis acid catalyzed tandem 1,5-hydride transfer/cyclization.
[reaction: see text] The scope and limitations of intramolecular hydro-O-alkylation of aldehyde substrates leading to spiroketals and bicyclic ketals and aminals is reported. The direct transformation of tertiary and sterically hindered secondary sp(3) C-H bonds into C-O bonds under the action of a catalytic amount of a variety of Lewis acids is described. The mechanism of these transformations is proposed to involve a tandem hydride transfer/cyclization sequence.
Pastine
Stefan J
SJ
Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
Sames
Dalibor
D
D000447:Aldehydes / Q000737:chemistry*; D000478:Alkylation; D002384:Catalysis; D003500:Cyclization; D007202:Indicators and Reagents; D015394:Molecular Structure; D013696:Temperature
D000447:Aldehydes; D007202:Indicators and Reagents