【简答题】Grignard试剂(卤代烃基镁)广泛运用于有机合成中,Grignard试剂的合成方法是:RX+Mg RMgX(Grignard试剂)。生成的卤代烃基镁与具有羰基结构的化合物(醛、酮等)发生反应,再水解就能合成各种指定结构的醇: 现以2-丁烯和必要的无机物为原料合成3,4-二甲基-3-己醇,进而合成一种分子式为C 10 H 16 O 4 的具有六元环的物质J,该物质具有对称性。合成线路如下: 请按...
【简答题】凯恩斯认为人们持有货币的动机有()、预防动机和投机动机。
【简答题】凯恩斯认为人们持有货币的动机有_( ) _、( ) 和_( ) 。
【单选题】The husband and wife in the story ______.
B.
went to the sales the year before
C.
often went to the sales to buy clothes
D.
were usually not short of money after Christmas
【简答题】The husband wished to invite ________________, but the woman did not agree and wished to have _____________ , while their daughter suggested: “____________________________________?
【单选题】有机化合物系统命名法中,不同的取代基,按照 ( ) 的顺序列出
【单选题】It was obvious that she and her husband were ______ and she wished she'd never married him.