Highly regioselective primary etherification of racemic propane-1,2-diol by the tin(II) bromide-catalyzed reaction with diazo[bis(4-methoxyphenyl)]methane and the resolution of enantiomers with the help of Pseudomonas cepacia lipase

The tin(II) bromide-catalyzed reaction of diazo[bis(4-methoxyphenyl)]methane with racemic propane-1,2-diol in 1,2-dimethoxymethane resulted in the highly regioselective etherification of the primary hydroxyl group. After tritylation of the minor 2-ether, 1-[bis(4-methoxyphenyl)]methoxypropane-2-ol was obtained in pure form. The enantiomeric mono-ethers were resolved by kinetic resolution by transacetylation with the help of Pseudomonas cepacia lipase.

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(S)-1-[Bis(4-methoxyphenyl)]methoxypropan-2-olC18H22O2[α]D20=+29 (c 1.1, CHCl3)Source of chirality: enzymatic reactionAbsolute configuration: (S)