Double diastereoselection in anti aldol reactions mediated by dicyclohexylchloroborane between an L-erythrulose derivative and chiral aldehydes.
نویسندگان
چکیده
Anti aldol reactions of an l-erythrulose derivative with several α-chiral aldehydes mediated by dicyclohexylboron chloride are examined. Good yields and stereoselectivities are observed. The results are best explained when the reactions are assumed to occur via boat-like transition states with minimization of 1,3-allylic strain and avoidance of syn pentane interactions.
منابع مشابه
Aldol Reactions between L-Erythrulose Derivatives and Chiral α-Amino and α -Fluoro Aldehydes: Competition between Felkin–Anh and Cornforth Transition States
Both matched and mismatched diastereoselection have been observed in aldol reactions of a boron enolate of a protected l-erythrulose derivative with several chiral α-fluoro and α-Amino aldehydes. Strict adherence to the Felkin–Anh model for the respective transition structures does not account satisfactorily for all the observed results, as previously observed in the case of α-oxygenatedaldehyd...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 10 34 شماره
صفحات -
تاریخ انتشار 2012