(4aR,4'S,6S,7aS)-tert-butyl 4-formyl-6-methoxymethoxy-2-(2-nitrophenylsulfonyl)-2'-oxo-1,2,4a,5,6,7a-hexahydrospiro(cyclopenta[c]pyridine-7,4'-oxazolidine)-3'-carboxylate                                                                                                                                                              在
                                                                                                                                                                                 
caesium carbonate   、                                                                                                  
苯硫酚                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
乙腈                                                                                  为溶剂,
                                                                                                                                                    反应 2.0h,
                                                                                                                以92%的产率得到(4'S,6S,7aS)-tert-butyl 4-formyl-6-methoxymethoxy-2'-oxo-1,2,4a,5,6,7a-hexahydrospiro(cyclopenta[c]pyridine-7,4'-oxazolidine)-3'-carboxylate