Test: Alkynes & Aromatic hydrocarbon(10 Sep) - JEE MCQ

Statement I : Treatment of either 1,2-dibromobutane or 2,2-dibromobutane with NaNH₂ gives the same 1-butyne.

Statement II : NaNH₂ forms salt with terminal alkyne which makes possible the above observation.

Statement l : C₆H₅MgBr with propyne gives 1-phenyl propyne.

Which set of reagent(s) in correct order would accomplish the following transformation?

What is true about the final major product of the reaction?

Which of the following sets of reagent when applied sequentially, on 2-butyne will produce a meso product?

Direction (Q. Nos. 15 - 20) This section contains 2 paragraphs, each describing theory, experiments, data, etc. Six questions related to the paragraphs have been given. Each question has only one correct answer among the four given options (a), (b), (c) and (d).

Passage I

Unlike alkenes, alkynes undergo nucleophilic addition as well as electrophilic addition as :

Q. Which of the following best describes what happens in the first step in the mechanism of reaction shown below?

Direction (Q. Nos. 21 - 24) This section contains 4 questions. When worked out will result in an integer from 0 to 9 (both inclusive).

Q. How many different isomeric alkynes on catalytic hydrogenation can give 2, 3, 4 -trimethyl heptane?