dimethylene

例句：

1. 1.This compound has a dimethylene bridge between the two carbon atoms.
   这个化合物在两个碳原子之间有一个二甲基桥。
2. 2.The molecule is made up of two dimethylene groups connected by a single bond.
   这个分子由两个通过单键连接的二甲基基团组成。
3. 3. Dimethylene chloride is used as a solvent in organic synthesis.
   二甲基氯用作有机合成中的溶剂。