反应详情

2-Trifluoromethylpiperazine (Jenneskens et al., Ref. 31c) was prepared through a four step route (Scheme 32). Using Lewis acid TiCl4, N,N′-dibenzylethylenediamine 54 reacted with trifluoropyruvates to afford hemiacetal 55, which was reduced at room temperature by Et3SiH in CF3COOH to lactam 56. LiAlH4 treatment then reduced lactam 56 to 1,4-dibenzyl-2-trifluoromethylpiperazine 57. Finally, hydrogenation of compound 57 in HOAc gave the desired product 2-trifluoromethylpiperazine 58.