Piperidines from acid-catalysed cyclisations: Pitfalls, solutions and a new ring contraction to pyrrolidines
نویسندگان
چکیده
منابع مشابه
Stereoselective synthesis of 2,4,5-trisubstituted piperidines by carbonyl ene and Prins cyclisations.
An approach to 2,4,5-trisubstituted piperidines is reported, in which the key step is the Prins or carbonyl ene cyclisation of aldehydes of the type 1. Prins cyclisation catalysed by concentrated hydrochloric acid in CH(2)Cl(2) at -78 degrees C afforded good yields of two of the four possible diastereomeric piperidines, with the 4,5-cis product 7 predominating in a diastereomeric ratio of up to...
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ژورنال
عنوان ژورنال: Tetrahedron Letters
سال: 2017
ISSN: 0040-4039
DOI: 10.1016/j.tetlet.2017.07.058