TY - JOUR
T1 - Stereoselective synthesis of highly substituted bicyclic γ-lactones using homoaldol addition of 1-(1-cycloalkenyl)methyl carbamates
AU - Özlügedik, M.
AU - Kristensen, Jesper Langgaard
AU - Reuber, J.
AU - Fröhlich, R.
AU - Hoppe, D.
PY - 2004/10/1
Y1 - 2004/10/1
N2 - Stereoselective addition of aldehydes 4 to metallated 1-(1-cycloalkenyl) methyl N,N-diisopropylcarbamates 1 gave cyclic homoaldol adducts 6. By applying the (-)-sparteine method, enantiomerically enriched products were obtained. These were oxidatively cyclized to diastereomerically pure ¿-lactones 8 via the ¿-lactol ethers 7. After deprotonation of ¿-lactones 8 with lithium hexamethyldisilazide, a further substitution was achieved. By trapping the lactone enolates 11 with ß-naphthylmethyl bromide, single diastereomers of ¿-lactones 12 were produced.
AB - Stereoselective addition of aldehydes 4 to metallated 1-(1-cycloalkenyl) methyl N,N-diisopropylcarbamates 1 gave cyclic homoaldol adducts 6. By applying the (-)-sparteine method, enantiomerically enriched products were obtained. These were oxidatively cyclized to diastereomerically pure ¿-lactones 8 via the ¿-lactol ethers 7. After deprotonation of ¿-lactones 8 with lithium hexamethyldisilazide, a further substitution was achieved. By trapping the lactone enolates 11 with ß-naphthylmethyl bromide, single diastereomers of ¿-lactones 12 were produced.
UR - http://www.scopus.com/inward/record.url?scp=5644250666&partnerID=8YFLogxK
U2 - 10.1055/s-2004-831170
DO - 10.1055/s-2004-831170
M3 - Journal article
AN - SCOPUS:5644250666
SP - 2303
EP - 2316
JO - Synthesis
JF - Synthesis
SN - 0039-7881
IS - 14
ER -