Versatile intramolecular aza-Prins and Prins cyclization of aryl epoxides: a facile synthesis of diaza-, oxa-aza-, and dioxa-bicycles.
Aryl epoxides undergo coupling smoothly with (E)-hex-3-ene-1,6-ditosylamide in the presence of 10 mol % p-TSA in 1,2-dichloroethane at 75 degrees C to produce the corresponding 1,5-ditosyl-octahydro-1H-pyrrolidino[3,2-c]pyridines in good yields with high trans-selectivity, whereas the coupling of (Z)-hex-3-ene-1,6-ditosylamide gave cis-fused octahydro-1H-pyrrolidino[3,2-c]pyridines predominantly. The use of readily available p-TSA makes this method simple, convenient, and practical.
Yadav
Jillu S
JS
Division of Organic Chemistry, Indian Institute of Chemical Technology, Hyderabad-500 007, India. yadavpub@iict.res.in
Borkar
Prashant
P
Chakravarthy
P Pawan
PP
Reddy
Basi V Subba
BV
Sarma
Akella V S
AV
Basha
Shaik Jeelani
SJ
Sridhar
Balasubramanian
B
Grée
René
R