1374219-32-5Relevant articles and documents
Enantioselective synthesis of (-)-CP-55940 via ruthenium-catalyzed asymmetric hydrogenation of ketones
Cheng, Li-Jie,Xie, Jian-Hua,Wang, Li-Xin,Zhou, Qi-Lin
, p. 1105 - 1113 (2012/05/21)
A new and efficient catalytic asymmetric synthesis of the potent cannabinoid receptor agonist (-)-CP-55940 has been developed by using ruthenium-catalyzed asymmetric hydrogenation of racemic α-aryl ketones via dynamic kinetic resolution (DKR) as a key step. With RuCl2-SDPs/ diamine [SDPs=7,7'-bis(diarylphophino)-1,1'-spirobiindane] catalysts the asymmetric hydrogenation of racemic α-arylcyclohexanones via DKR provided the corresponding cis-β-arylcyclohexanols in high yields with up to 99.3% ee and >99:1 cis-selectivities. Both ethylene ketal group at the cyclohexane ring and ortho-methoxy group at the phenyl ring of the substrates 6 have little effect on the selectivity and reactivity of the hydrogenations. Based on this highly efficient asymmetric ketone hydrogenation, (-)-CP-55940 was synthesized in 13 steps (the longest linear steps) in 14.6% overall yield starting from commercially available 3-methoxybenzaldehyde and 1,4-cyclohexenedione monoethylene acetal. Copyright
