3.5- diaryl-isoxazolines

The catalytic reduction of 2-methyl-3-phenyl-3-isoxazoline (159) produced /3-hydroxypropiophenone (160) (74CPB70). Ring fission also occurred on base treatment of the 3,5-diaryl-3-isoxazoline (161) to give the a,/3-unsaturated oxime (162) (70CI(L)624). 

Shibata and coworkers [135] described the asymmetric phase-transfer catalytic synthesis of trifluoromethyl-substituted 2-isoxazolines 100 by an enantioselective conjugate addition of hydroxylamine to trifluoromethylated enones 99 and subsequent intramolecular formation of the imine, whereas Briere et al. [136] developed a facile method for the straightforward enantioselective synthesis of 3,5-diaryl pyrazoHnes 102 by phase-transfer-catalyzed conjugate addition of N-Boc-hydrazine... 

---