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in the above query the heteroatom bromine should only be considered as functional group and should be given the least number, why in the case the double bond is given the least number??
i can`t understand. pls explain

Asked by my3shyll | 15th Feb, 2017, 07:51: PM

Expert Answer:

The order of preference of functional groups is as follows:

−SO3H>−COOH>−COOR>−COX>−COCl>−CONH2>−CHO>−CN>>C=O>−OH>−SH>−NH2>C=C>−C≡C−>−NO2>−NO>−X

Answered by Vaibhav Chavan | 16th Feb, 2017, 11:03: AM