The degree of unsaturation (double bond equivalents) of 4-nitrobenzoyl chloride, O2N-C6H4-COCl (molecular formula C7H4ClNO3), is to be calculated using the formula (2C+2+N-H-X)/2. Give the answer to the nearest integer.

JEE Main levelNumerical answerDifficulty 2 of 3si014

The degree of unsaturation (double bond equivalents) of 4-nitrobenzoyl chloride, $O X_{2} N - C X_{6} H X_{4} - COCl$ (molecular formula $C X_{7} H X_{4} ClNO X_{3}$ ), is to be calculated using the formula $(2 C + 2 + N - H - X) /2$ . Give the answer to the nearest integer.

Numerical answer type, tolerance 0.5.

For

C X_{7} H X_{4} ClNO X_{3}

: C = 7, H = 4, N = 1, X = 1, so DBE

= (14 + 2 + 1 - 4 - 1) /2 = 12/2 = 6

. This agrees with structure: ring (4) +

C = O

(1) +

N = O

of the nitro group (1) = 6.