【简答题】请将下面的句子改成倒装句 They had hardly heard the news when they rushed out into the street.
【简答题】A. Fill in each blank with a proper temporal conjunctive (用 时间连词填空,如:just as、when、before、after、while、as soon as、since、once、soon after、until等 ) 。 They had hardly started to work the trouble began.
【单选题】The two men had hardly had time to ________what had happened when they were thrown violently into the sea.
【简答题】B. Fill in each blank with a proper temporal conjunction ( 用时间连词填空 ) 。 After Once when until soon after 1. They kept on working it because completely dark. 2. They had hardly started to work the ...
【判断题】Friedel-Crafts 烃化反应中烃化剂的活性顺序为: RI>RBr>RCl>RF
【单选题】Hardly ______ when the door suddenly closed.
【单选题】If they had worked hardly, they die project ahead of time.
【单选题】下列说法不正确的是()
A.
酰氯和酸酐都可以作为Friedel-Crafts酰基化试剂
B.
Friedel-Crafts烷基化反应中AlCl3,ZnCl2,H3PO4,H2SO4是常用催化剂
C.
卤代烃,烯烃和醇都可以用作Friedel-Crafts烷基化的烷基化试剂
D.
Friedel-Crafts反应是典型的自由基反应
【简答题】羟乙基化试剂是 A. 卤代烃 B. 环氧乙烷 C. 硫酸二乙酯 D. 芳磺酸酯 2 .常用于制备联芳胺的反应是 A. 乌尔曼反应 B. Friedel -Crafts 反应 C. Dele′pine 反应 D. Gabriel 反应 3 . Williamson 反应的产物是 A. 烃类 B. 酰胺类 C. 酯类 D. 醚类 4 .羰基化合物 α 位 C- 烃化的反应条件是 A. 碱性 B. 酸性...