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[reaction: see text] A remarkably general lithium heteroatom assisted TMSCN or TBSCN addition to aldehydes and ketones has been discovered. The process provides excellent selectivities and high rates. Conformationally constrained ketones such as camphor, fenchone, and nopinone give excellent diastereoselectivities with TMSCN. Reduction of 2 provided diastereopure amino alcohol 3 in good yield. alpha- and beta-Methyl cyclohexanones with TBSCN-LiOR afford high diastereoselectivities and yields.

The development of a process for the use of N,N-diethylanilineborane (DEANB) as a borane source for the enantioselective preparation of a key intermediate in the synthesis of (R,R)formoterol L-tartrate, bromohydrin 2, from ketone 3 on kilogram scale is described. DEANB was found to be a more practical, safer, and higher-quality reagent when compared to other more conventional borane sources: borane-THF and borane-DMS.