Homochiral ligands derived from cis-1-phenylcyclohexane-1,2-diol and cis-2-azido-2-phenylcyclohexanol

Article abstract of DOI:10.1016/S0957-4166(97)00552-1

Homochiral ligands (R,R)-2, (R,R)-3a, (R,R)-3b, (S,S)-4a, and (S,S)-4b were prepared from cis-1-phenylcyclohexane-1,2-diol or cis-2-azido-2-phenylcyclohexanol and were tested as ligands for the nucleophilic addition of alkyllithiums to benzaldehyde 4-anisidineimine. While moderate enantioselectivities (up to 43% e.e.) were observed with (R,R)-3b and (S,S)-4a, (R,R)-2 and (R,R)-3a did not show enantioselectivities. Homochiral secondary amines (S,S)-6a and (S,S)-6b were also prepared from cis-2-azido-2-phenylcyclohexanol. Moderate enantioselectivities (up to 50%) were observed when they were used as chiral lithium amide base precursors for the deprotonation of 4-t-butylcyclohexanone.