On June 17, 2005, Mutti, Stephane; Malpart, Joel; Lavigne, Michel published a patent.Recommanded Product: tert-Butyl (4-(trifluoromethyl)phenyl)carbamate The title of the patent was Method for preparation of thiazolo[3,4,5-de][4,1]benzothiazepines via direct cyclization of tert-butyl 2-hydroxymethylphenylcarbamates with thioglycolic acid in the presence of p-toluenesulfonic acid. And the patent contained the following:
The invention is related to the preparation of the well-known anticonvulsants thiazolo[3,4,5-de][4,1]benzothiazepine derivatives, in particular I•MeSO3H and II•MeSO3H, and their enantiomers and pharmaceutically acceptable salts via direct cyclization of 2-hydroxymethyl phenylcarbamates, e.g. tert-Bu 2-hydroxymethylphenylcarbamate (III) with thioglycolic acid (IV) in the presence of p-toluenesulfonic acid. The advantages include reduced number of steps and simple purification Thus, was prepared, in 58% global yield, in 8 steps: (1) BOC-protection of 4-trifluoromethylaniline with di-tert-Bu dicarbonate; (2) formylation with DMF; (3) reduction of the aldehyde with NaBH4; (4) cyclization of III with IV in the presence of p-toluenesulfonic acid in toluene; (5) reduction of amide V with NaBH4 in the presence of MeSiCl/THF; (6) cyclization of tetrahydrobenzothiazepine with KSCN in the presence of Br2/AcOH; (7) oxidation of thiazolobenzothiazepine with O3 in CH3CN/H2O; (8) methanesulfonate formation by treatment with MeSO3H in acetone/H2O. The experimental process involved the reaction of tert-Butyl (4-(trifluoromethyl)phenyl)carbamate(cas: 141940-37-6).Recommanded Product: tert-Butyl (4-(trifluoromethyl)phenyl)carbamate
The Article related to thiazolobenzothiazepine preparation cyclization hydroxymethylphenylcarbamate thioglycolic acid toluenesulfonic acid catalyst, Heterocyclic Compounds (More Than One Hetero Atom): Other 7-Membered Rings and other aspects.Recommanded Product: tert-Butyl (4-(trifluoromethyl)phenyl)carbamate
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