The question of the regiodirection of the [2+3] cycloaddition reaction of triphenylnitrone to nitroethene

Experimental and Theoretical Mechanistic Study on the Thermal Decomposition of 3,3-diphenyl-4-(trichloromethyl)-5-nitropyrazoline

“…This observation is unexpected, because the presence of CCl 3 group generally stabilises the heterocyclic systems in the comparison with analogs with CH 3 or other groups. This was confirmed inter alia for series of 2,3,3-triphenyl-4-nitro-5- R -isoxazolidines [ 9 , 10 , 11 ]. On the other hand, examples which are available in the literature, confirm relatively high energy of the activation for the dehydrochlorination reactions from CCl 3 functionalised molecules.…”

Experimental and Theoretical DFT Study on Synthesis of Sterically Crowded 2,3,3,(4)5‐Tetrasubstituted‐4‐nitroisoxazolidines via 1,3‐Dipolar Cycloaddition Reactions Between Ketonitrones and Conjugated Nitroalkenes

“…The literature describes many examples of 2,3‐disubstituted , 2,3,3‐trisubstituted as well as 2,3,5‐trisubstituted 4‐nitroisoxazolidines . However, sterically crowded 2,3,3,(4)5‐tetrasubstituted‐4‐nitroisoxazolidines are practically not known.…”

Recent progress in the field of cycloaddition reactions involving conjugated nitroalkenes

“…It should be underlined, that the application of an ionic liquid allows to shorten the conversion time of substrates to 10 minutes in comparison to toluene solution 18 . Jasiński 19 also carried out [3+2] cycloaddition reactions of C,C,N-triphenylnitrone to nitroethene (Scheme 4). It was reported that, in the contrast to earlier reports 20 , the process is full regioselectively independently of the temperature.…”