Preparation of 2-Substituted 4-Chloro-5-Formylimidazole and 5-Formylimidazole
申请人:Rajnikant Vyas Janmejay
公开号:US20080200690A1
公开(公告)日:2008-08-21
The invention relates to a preparation process for 2-substituted 5-formylimidazoles, wherein the intermediate high-pressurized synthesis of an 2-substituted 4-hydroxymethylimidazole as known in the art is conveniently avoided, and wherein much higher yields are obtained. Instead, it is proposed to prepare such 2-substituted 5-formylimidazoles via a one-pot synthesis involving 2-substituted 4-chloro-5-formylimidazole, thereby employing an additional hydrodehalogenation step. Moreover, it is found that the yield and purity of 2-substituted 4-chloro-5-formylimidazole itself can be significantly improved using a triflate catalyst in the preparation process.
A process for the preparation of 2-substituted 5-chloroimidazole-4-carbaldehydes of the general formula: ##STR1## in which glycine is reacted with an imido ester of the general formula: ##STR2## and the resultant intermediate is converted into the product by a Vilsmeier reagent. The 2-substituted 5-chloroimidazole-4-carbaldehydes are valuable intermediates for the preparation of pharmaceuticals or herbicidally active compounds.
PREPARATION AND UTILITY OF SUBSTITUTED PHENYLTETRAZOLES
申请人:Gant Thomas G.
公开号:US20080132555A1
公开(公告)日:2008-06-05
Disclosed herein are substituted phenyltetrazoles of Formula I, processes of preparation thereof, pharmaceutical compositions thereof, and the methods of their use thereof.