An experimental and theoretical study of the enantioselective deprotonation of cyclohexene oxide with isopinocampheyl-based chiral lithium amides.
The mechanism of the enantioselective deprotonation of cyclohexene oxide with isopinocampheyl-based chiral lithium amide was studied by quantum chemical calculations. The transition states of eight molecules were fully optimized at the ab initio HF/3-21G and density functional B3LYP/3-21G levels with Gaussian 98. The activation energies were calculated at the B3LYP/6-31+G(3df,2p)//B3LYP/3-21G level. We found the theoretical evaluation to be consistent with the experimental data. At the best case, an enantiomeric excess of up to 95% for (R)-2-scyclohexen-1-ol was achieved with (-)-N, N-diisopinocampheyl lithium amide.
Xiao
Ying
Y
Department of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, USA.
Jung
Dawoon
D
Gund
Tamara
T
Malhotra
Sanjay V
SV
D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D053138:Cyclohexenes / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011522:Protons; D013237:Stereoisomerism
D000577:Amides; D053138:Cyclohexenes; D011522:Protons; C007193:cyclohexene oxide; D008094:Lithium