Compounds Containing Nitrogen

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Starting compound is anitrile:Ph–(CH₂)₃–CN.DIBAL-H (1 eq), then H₂Oreduces a nitrileselectively to an aldehyde(stops at aldehyde with controlled conditions):Ph–(CH₂)₃–CHOZn–Hg / conc. HCl (Clemmensen reduction)reduces the aldehydeto the corresponding alkane:Ph–(CH₂)₃–CH₃✅Major product = n-butylbenzene (Ph–CH₂–CH₂–CH₂–CH₃)→Option A