Facile syntheses of 4-(trifluoromethyl)-L-spinacine and 4-(trifluoromethyl)spinaceamine
作者:Shozo Fujii、Yasuo Maki、Hiroshi Kimoto、Louis A. Cohen
DOI:10.1016/s0022-1139(00)81956-9
日期:1987.5
Reaction of L-histidine with trifluoroacetaldehyde ethyl hemiacetal (TFAE) in boiling water provides 4-(trifluoromethyl)-L-spinacine, 4-(trifluoromethyl)-L-4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid, in near quantitative yield. The product contains two diastereoisomers in the ratio 68 : 32. The isomers were separated (silica gel) as their protected derivatives, 5-N-(trifluoroac
Synthesis of imidazo[4,5-<i>c</i>]pyridines with a trifluoromethyl group at C-4 and/or C-6
作者:Rakesh K. Gautam、Shozo Fujii、Masakazu Nishida、Hiroshi Kimoto、Louis A. Cohen
DOI:10.1002/jhet.5570310235
日期:1994.3
dehydrogenation with selenium dioxide leads to 4-(trifluoromethyl)-1H-imidazo[4,5-c]pyridine (42%). Fluorination with sulfur tetrafluoride of L-spinacine, obtained from the condensation of L-histidine with formaldehyde, affords 6-(trifluoromethyl)spinacamine, which can be converted to 6-(trifluoromethyl)-1H-imidazo[4,5-c]pyridine with selenium dioxide (49%). Application of the sequential reactions to 4
组胺与三氟乙醛的热缩合得到4-(三氟甲基)spinacamine,随后用二氧化硒脱氢得到4-(三氟甲基)-1 H-咪唑并[4,5- c ]吡啶(42%)。由L-组氨酸与甲醛缩合得到的L-丝氨酸碱的四氟化硫氟化,得到6-(三氟甲基)spinacamine,可以将其转化为6-(三氟甲基)-1 H-咪唑并[4,5- c ]吡啶与二氧化硒(49%)。将顺序反应应用于4-(三氟甲基)-L-丝氨酸碱,得到4,6-双(三氟甲基)-1 H-咪唑并[4,5- c]吡啶。在四氟化硫氟化过程中也发生了四氢吡啶环的脱氢反应。