Substrate-directed diastereoselective

Breit reported a substrate-directed diastereoselective hydroformylation of acyclic methallylic and homomethallylic alcohols protected by 2-(diphenylphosphanyl)benzoyl group (63 and 64) using a P(OPh)3/Rh(acac)(GO)2 system and isolated the corresponding < ///-aldehydes in good diastereoselectivity (Table 11, up to 9614 = They... 

With the aid of the o-DPPB functionality a substrate-directed diastereoselective hydroformylation of methallylic alcohol derivatives could be achieved with high levels of acyclic stereocontrol to provide the syn-aldehydes 6 as the major diastereomers [10]. 

For substrate-directed diastereoselective hydroformylation of cyclic systems see... 

Most reports on diastereoselective oxidation of sulfides are substrate-directed. Diastereoselectivity has been achieved by either steric- or neighboring-group participation.21 Incipient hydrogen bonding between the substrate hydroxyl group and the incoming percarboxylic acid has been evoked to explain the high diastereoselectivity observed in the oxidation of 10-exo-hydroxy-bornyl- derivatives 7 and 9 (Scheme 1). The oxidation of 9 with m-CPBA in MeOH occurs without stereoselectivity. 

A new epoxidation method has been reported involving the use of a polyleucine catalyst in the epoxidation of 133. The use of the immobilized D- or L-polyleucine can overcome the inherent substrate-directed diastereoselectivity in the reaction <1999TL1779>. 

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