反应详情

2-Trifluoromethylpiperazine (Jenneskens et al., Ref. 31c) was prepared through a four step route (Scheme 6). Using Lewis acid TiCl4, N,N′-dibenzylethylenediamine 11 reacted with trifluoropyruvates 12 to afford hemiacetal 13, which was reduced at room temperature by Et3SiH in CF3COOH to lactam 14. LiAlH4 treatment then reduced lactam 14 to 1,4-dibenzyl-2-trifluoromethylpiperazine 15. Finally, hydrogenation of compound 15 in HOAc gave the desired product 2-trifluoromethylpiperazine 16.