Synthesis of Ketone from Alkyl Halide Using α-Chloro Nitrone as Oxidizing Reagent: A New Approach

Synthesis of Some Novel Class of Regioselective Spiro Isoxazolidine Derivatives via 1,3‐Dipolar Cycloaddition Reaction of N‐Benzyl‐C‐fluoro‐substituted Phenyl Nitrones in Ionic Liquid

“…To execute the proposed study, various fluoro‐substituted benzaldehydes and N‐ benzylhydroxylamine were employed for the synthesis of N‐ benzyl‐ C ‐fluoro‐substituted phenyl nitrones ( 1 ) following our reported methodology . This was followed by 1,3‐dipolar cycloaddition reactions of nitrone 1 with different new substituted active alkenes (α‐ N ‐substituted furan derivatives) commonly called enamines ( 2 ) for the synthesis of a variety of new spiro isoxazolidine derivatives ( 3 ) in ionic liquid by employing our reported protocol (Scheme , Table ).…”

“…In these synthesis, for the first time, we have introduced novel α‐ N ‐substituted furan derivatives 2 (also known as enamines) as active dipolarophiles in the 1,3‐dipolar cycloaddition reaction with N ‐benzyl‐ C ‐fluoro‐substituted phenyl nitrones ( 1 ) for the regioselective synthesis of 5‐spiro isoxazolidines ( 3 ) at room temperature with an excellent yield (Scheme , Table ). The newly reported dipolarophiles were obtained as side products during aldehyde and ketone synthesis using N ‐substituted nitrones as active oxidizing agents, and the preliminary activity of the dipolarophiles were also tested . The reactions of nitrone 1 with newly reported α‐ N ‐substituted furan derivatives ( 2 ) as dipolarophiles are found to be highly regioselective to form solely 5‐spiro isoxazolidine derivatives ( 3 ).…”

“…We have also tested synthesis of spiro isoxazolidine derivatives using other simpler N ‐phenyl nitrones (R = NH 2 ; Ph; –CHCl(CH 2 ) 3 OH) with new dipolarophiles (entry 9 & 10 ; Table ) for comparing the course of the reaction with N‐ benzyl‐ C ‐fluoro‐substituted phenyl nitrones ( 1 ). It has been observed that all the reactions were equally efficient as per as time and yields are concerned in ionic liquid.…”

“…Isoxazolidines are also found to exhibit medicinal activities such as antibacterial, anticonvulsant, antibiotic, antituberculer, and antifungal activity . As a part of our ongoing research program to develop new methodologies for the synthesis of new molecules , herein, we report regioselective synthesis of some new spiro isoxazolidine derivatives ( 3 ) using N‐ benzyl‐ C‐ fluoro‐substituted phenyl nitrones ( 1 ) with α‐ N ‐substituted furan derivatives ( 2 ) via 1,3‐dipolar cycloaddition reaction in good to excellent yields in ionic liquid (Scheme , Table ). Furthermore, these regioselective spiro isoxazolidine derivatives are found to have vast synthetic potential as they could be converted into synthetically more important new spiro 1,3‐amino alcohols ( 4 ).…”

Highly Stereoselective Synthesis of New Aziridines via Baldwin Rearrangement and Their Potential Biological Activities

“…The wealthy literature on cycloaddition reactions of nitrones for the synthesis of isoxazolidine, isoxazoline derivatives, and their further applications have been widely illustrated while conversions of isoxazoline derivatives to aziridines are of tremendous interest in this chemistry . As a part of our ongoing research program to develop new methodologies in organic synthesis , herein, we report stereoselective synthesis of new N‐ substituted aziridine derivatives from isoxazolines via Baldwin rearrangement and their biological activities (Scheme ; Table ). The newly reported N‐ substituted aziridine derivatives are obtained as single diastereoisomer when the isoxazoline derivatives are exposed to microwave irradiation for 5–8 min at 90–130°C.…”