JEE Main · 2019 · 08 Apr 2019 · Shift 2 · Biomolecules

The major product in the following reaction is:

(A)(see structure)
(B)(see structure)
✓ Correct
(C)(see structure)
(D)(see structure)

Answer: (B)

Solution

The nitrogen marked in the purine ring is the most electron-rich one and still carries a hydrogen. Base (

OH X^{-}

) removes that N-H proton, and the resulting nucleophilic nitrogen then attacks the methyl carbon of

CH X_{3} I

in a substitution step. The methyl group ends up on that nitrogen, giving the N-methylated purine as the major product.

JEE Main · 2019 · 08 Apr 2019 · Shift 2 · Single correct option

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