3,5-dichloro-2-(chloromethyl)pyridine   、                                                                                      ethyl (5RS,6RS)-3-oxo-6-(trifluoromethyl)-2,3,5,6,7,8-hexahydro[1,2,4]triazolo[4,3-a]pyridine-5-carboxylate                                                                                                                                                              在
                                                                                                                                                                                 
caesium carbonate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
乙腈                                                                                  为溶剂,
                                                                                                                                                                                        生成                                                 ethyl (5RS,6RS)-2-[(3,5-dichloropyridin-2-yl)methyl]-3-oxo-6-(trifluoromethyl)-2,3,5,6,7,8-hexahydro[1,2,4]triazolo[4,3-a]pyridine-5-carboxylate