Generation of ketenes from acid chlorides using NaH/crown ether shuttle-deprotonation for use in asymmetric catalysis.
[reaction: see text] We describe methodology for the in situ generation of reactive monosubstituted ketenes from acid chlorides through a shuttle deprotonation process using NaH as an inexpensive stoichiometric base and a crown ether cocatalyst. We have successfully applied this new procedure to the catalytic, asymmetric synthesis of beta-lactams and alpha-haloesters.
Taggi
Andrew E
AE
Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Wack
Harald
H
Hafez
Ahmed M
AM
France
Stefan
S
Lectka
Thomas
T
D000475:Alkenes / Q000138:chemical synthesis; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry; D004988:Ethers, Cyclic / Q000737:chemistry*; D007202:Indicators and Reagents; D007659:Ketones / Q000138:chemical synthesis; D007769:Lactams / Q000138:chemical synthesis; D011522:Protons
D000475:Alkenes; D002712:Chlorides; D004988:Ethers, Cyclic; D007202:Indicators and Reagents; D007659:Ketones; D007769:Lactams; D011522:Protons