The term removed refers to the number of generations separating the cousins themselves. So your first cousin once removed is the child (or parent) of your first cousin. Your second cousin once removed is the child (or parent) of your second cousin. And your first cousin twice removed is the grandchild (or grandparent) of your first cousin. Clearly, it doesn't take many generations before your family tree is a bit unwieldy.
A molecule can have more than one acyl halide functional group. For example, adipoyl dichloride, usually simply called adipoyl chloride, has two acyl chloride functional groups; see the structure at right.It is the dichloride (i.e., double chloride) of the 6-carbon dicarboxylic acid adipic acid.n acyl halide (also known as an acid halide) is a chemical compound derived from an oxoacid by replacing a hydroxyl group with a halide group. If the acid is a carboxylic acid, the compound contains a âCOX functional group, which consists of a carbonyl group singly bonded to a halogen atom.
It also results from the hydrolysis of silylethers and other silyl-protected functional groups. HMDSO can be converted back to the chloride by reaction with Me2SiCl2. Hexamethyldisiloxane is mainly used as source of the trimethylsilyl functional group (-Si(CH3)3) in organic synthesis. For example, in the presence of acid catalyst, it converts alcohols and carboxylic acids into the silyl ethers and silyl esters, respectively.