Optical resolution of hexamethylbiphenol by cholesterol esterase and porcine pancreas lipase

Both enantiomers of 2,2'-dihydroxy-4,4',5,5',6.6'-hexamethybiphenyl (2), a potentially useful chiral synthon, were obtained with > 99% ee in high enantioselectivity by cholesterol esterase or porcine pancreas lipase (PPL)-mediated hydrolysis of the corresponding (+/-)-dipentanoate or (+/-)-dihexanoate, respectively. Absolute configuration of(S)-3-bromo-2,6'-dimethoxy-4,5,6,2',3',4'-hexamethyl-biphenyl (2h) was determined by X-ray analysis. (c) 2008 Published by Elsevier B.V.