486-16-8Relevant articles and documents
Transition-Metal Free Chemoselective Hydroxylation and Hydroxylation-Deuteration of Heterobenzylic Methylenes
Fu, Yiwei,Li, Hao,Liu, Yonghai,Mang, Zhiguo,Shi, Lei,Sun, Chengyu,Yu, Yang
supporting information, p. 8127 - 8131 (2020/11/03)
We developed an approach for direct selective hydroxylation of heterobenzylic methylenes to secondary alcohols avoiding overoxidation to ketones by using a KOBu-t/DMSO/air system. Most reactions could reach completion in several minutes to give hydroxylated products in 41-76% yields. Using DMSO-d6, this protocol resulted in difunctionalization of heterobenzylic methylenes to afford α-deuterated secondary alcohols (>93% incorporation). By employing this method, active pharmaceutical ingredients carbinoxamine and doxylamine were synthesized in two steps in moderate yields.
Highly selective metalations of pyridines and related heterocycles using new frustrated lewis pairs or tmp-zinc and tmp-magnesium bases with bf 3·oet2
Jaric, Milica,Haag, Benjamin A.,Unsinn, Andreas,Karaghiosoff, Konstantin,Knochel, Paul
supporting information; experimental part, p. 5451 - 5455 (2010/09/16)
(Figure Presented) Efficient and selective: Frustrated Lewis pairs based on BF3·OEt2 and LiCl-com-plexed tmpMg or tmpZn amides (tmp = 2,2,6,6-tetramethylpiperidyl) allow the efficient and regioselective metalation of various functionalized N heterocycles (see scheme for examples). Moreover, such metalations carried out in the presence or absence of BF 3·OEt2 enable a complete switch of regioselectivity, thus allowing complementary fuctionalization.
[1,2]-Anionic rearrangement of 2-benzyloxypyridine and related pyridyl ethers
Yang, Jingyue,Dudley, Gregory B.
scheme or table, p. 7998 - 8000 (2010/03/01)
(Chemical Equation Presented) An anionic rearrangement of 2-benzyloxypyridine is described. Pyridine-directed metalation of the benzylic carbon leads to 1,2-migration of pyridine via a postulated associative mechanism (addition/elimination). Several aryl pyridyl carbinols were obtained in high yields. A formal synthesis of carbinoxamine, an antihistamine drug used for the treatment of seasonal allergies and hay fever, emerges from this methodology.