3. Number the substituents and write the name, listing substituents alpha betically. 4. Acid halide substituents attached to rings are named using the suffix -carbonyl Several simple examples are shown below: Z-ethyipe chloride 3-bromo-2-ethyibutanoyl CH 2-cycloherenecarbomyl chloride 5-bromo-2-methyit fluoride In the first example, the parent chain is a pentane and the acy l group is assigned as carbon #1. On the pentane parent, there is an ethy l group in position #2 hence the name, 2-ethy lpentanoyl chloride In the second example, there are two potential four-carbon chains; in this case, the chain with the most substituents is selected as parent, (a butanoyl bromide). Attached to the chain at carbon #2 is an ethyl group and at carbon #3, a bromine; hence the name 3-bromo-2-ethy l butanoyl bromide In the third example, the acyl group is attached to a cycloalkene ring and will therefore be named as a carbonyl chloride"substituent (rule #4). The parent ring is a cyclohexene; letting the acyl group be carbon #l, the name is 2-cyclohexenecarbonyl chloride In the last example, the name is based on benzoic acid as the parent. In this case, we simply number the substituents to give the lowest number sequence at the first point of difference and arrange alphabetically 5-bromo-2-methy benzoyl fluoride Simple acid anhydrides are named by replacing the ending acid with anhydride Select the longest continuous carbon chain, conta ining the carboxy lic acid group, and derive the parent name by replacing the -e ending with -oic anhydride 2. Num ber the carbon chain, beginning at the end nearest to the acyl grou3. Number the substituents and write the name, listing substituents alphabetically. 4. Acid halide substituents attached to rings are named using the suffix -carbonyl. Several simple examples are shown below: In the first example, the parent chain is a pentane and the acyl group is assigned as carbon #1. On the pentane parent, there is an ethyl group in position #2; hence the name, 2-ethylpentanoyl chloride. In the second example, there are two potential four-carbon chains; in this case, the chain with the most substituents is selected as parent, (a butanoyl bromide). Attached to the chain at carbon #2 is an ethyl group and at carbon #3, a bromine; hence the name 3-bromo-2-ethylbutanoyl bromide. In the third example, the acyl group is attached to a cycloalkene ring and will therefore be named as a "carbonyl chloride" substituent (rule #4). The parent ring is a cyclohexene ; letting the acyl group be carbon #1, the name is 2-cyclohexenecarbonyl chloride. In the last example, the name is based on benzoic acid as the parent. In this case, we simply number the substituents to give the lowest number sequence at the first point of difference and arrange alphabetically; 5-bromo-2-methylbenzoyl fluoride. Simple acid anhydrides are named by replacing the ending "acid" with "anhydride". 1. Select the longest continuous carbon chain, containing the carboxylic acid group, and derive the parent name by replacing the -e ending with -oic anhydride. 2. Number the carbon chain, beginning at the end nearest to the acyl group