Trifluoromethoxy-substituted anilines undergo hydrogen/lithium permutation (''metalation'') with optional site selectivity depending on the N-protective group employed. N-tert-Butoxycarbonyl-2- and -4-(trifluoromethoxy)aniline react with tert-butyllithium. at the nitrogen-adjacent 6- and 2-position affording, after electrophilic trapping, products 1-6. In contrast, deprotonation of the para isomer occurs at the oxygen-neighboring 3-position, giving rise to the acid 12, when the amino group is carrying two trimethylsilyl groups. sec-Butyllithium attacks 3-trifluoromethoxy-N-mono-(trimethylsilyl)aniline at the 2-position, but 3-trifluoromethoxy-N,N-bis(trimethylsilyl)aniline at the 4-position to provide respectively the acids 10 and 11 after carboxylation. The synthesis of two new benzodiazepines illustrates (19 and 22) the preparative potential of the aniline functionalization mediated by organometallic reagents.
US6369221B1
申请人:——
公开号:US6369221B1
公开(公告)日:2002-04-09
Thiazolobenzoheterocycles, preparation and medicines containing same
申请人:Aventis Pharma S.A.
公开号:US06369221B1
公开(公告)日:2002-04-09
Disclosed are thiazolobenzoheterocycles of the general formula
Including their isomers, racemates, enantioners and salts thereof, as well as processes for preparing these compounds and medicaments containing them. Also disclosed are novel intermediates for preparing the foregoing compounds, these intermediates having the formula