Quantum chemical modeling of chiral catalysis. Part 7. On the effects controlling the coordination of borane to chiral oxazaborolidines used as catalysts in the enantioselective reduction of ketones

1,2-Amino Alcohols and Their Heterocyclic Derivatives as Chiral Auxiliaries in Asymmetric Synthesis

“…33,236,[307][308][309][310][311][312][313][314][315][316][317][318] The proposed mechanism for the reduction is summarized in Scheme 57. 308,309,[319][320][321][322][323][324][325] Other oxazaborolidines, such as 69-72, are also excellent catalysts for the asymmetric reduction of ketones to secondary alcohols. [307][308][309]313,314,317,[326][327][328][329][330][331][332][333][334][335][336][337][338] Oxazaborole-boranes give high degrees of asymmetric reduction with dialkyl ketones and are stable and amenable to scale up, 333 as do terpene-based oxazaborolidines, although enantioselectivity is not as high with the latter.…”

Polypropylene–intumescent flame‐retardant composites based on meleated polypropylene as a coupling agent

“…Some successful quantum chemical modeling studies on the enantioselective reduction of prochiral ketone with borane catalyzed by oxazaborolidine were carried out by means of the ab initio molecular orbital method 5–18, and the mechanism of catalysis was suggested by Corey et al 19. However, all the reported results involve only the reduction of one carbonyl bond.…”

Quantum chemical study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine. Part 1. Structures of catalyst-borane-keto oxime ether adducts

“…As for quantum chemical modeling studies on the enantioselective reduction of prochiral ketone with borane catalyzed by oxazaborolidine, some successful work was done by means of the ab initio molecular orbital method 5–18. Up to now, all the reported studies are computations of the enantioselective reduction of prochiral ketone with borane catalyzed by oxazaborolidine, and only one carbonyl bond is reduced in the reaction.…”