Double conjugate addition of dithiols to propargylic carbonyl systems to generate protected 1,3-dicarbonyl compounds.
The work describes the efficient double conjugate addition of ethane and propane dithiols in the presence of sodium methoxide to a wide variety of propargylic carbonyl containing compounds. The products of these reactions are differentiated, 1,3-dicarbonyl systems useful for various synthesis programs. By judicious use of hydroxylated substrates tandem cyclization occurs to afford tetrahydropyran lactols or, in the case of hydroxy-substituted propargylic esters, lactones. The corresponding amino-substituted propargylic aldehydes gives piperidine derivatives upon double conjugate addition tandem cyclization.
Sneddon
Helen F
HF
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, U.K.
van den Heuvel
Alexandra
A
Hirsch
Anna K H
AK
Booth
Richard A
RA
Shaw
David M
DM
Gaunt
Matthew J
MJ
Ley
Steven V
SV
D000447:Aldehydes / Q000737:chemistry*; D003500:Cyclization; D015394:Molecular Structure; D010880:Piperidines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000737:chemistry*
D000447:Aldehydes; D010880:Piperidines; D013438:Sulfhydryl Compounds