61.Give the major product of the following reaction: [E]-2-pentence+ CH₂I₂/Zn(Cu)→ ?
(A)cis-1-Ethyl-2-methylcyclopropane
(B)trans-1-Ethyl-2-methylcyclopropane
(C)1-Ethyl-1-methylcyclopropane
(D)An equimolar mixture of product {A} and {B}
(E)None of these

57.Which alkyne yields butanoic acid (CH3CH2CH2CO2H) as the only organic product upon treatment with ozone followed by hydrolysis? (A)1-Butyne (B)4-Octyne (C)1-Pentyne (D)2-Hexyne (E)None of these ..

58.Which of the following produces a significant amount of acetylide ion on reaction with acetylene? (A)Conjugate base of CH3OH (pKa16) (B)Conjugate base of H2 (pKa35) (C)Conjugate base of H2O (pKa16) (D)Both {A} and {C} (E)Both {A} and {B}

59.Hydrogenation of cyclohexene releases 120kJ/mol of heat. Which of the following most likely represents the observed heat of hydrogenation of 1,3-cyclohexadiene? (A)232kJ/mol (B)239kJ/mol (C)247kJ/mol (D)120kJ/mol (E)142kJ/mol

60.Arrange the following intermediates in order of decreasing basicity (strongest→weakest): (A)B > A > D > (B)D > A > B > C (C)C > D > A > B (D)C > B > D >A (E)D > C >B >A

62.Which of the following would yield a secondary alcohol after the indicated reaction, followed by aqueous hydrolysis if necessary? (A)LiAlH4 + a ketone (B)CH3CH2MgBr + an aldehyde (C)2-Butene + mercury(II)acetate, then NaBH4, HO (D)All of these (E)None of these

63.Which of the esters shown, after reduction with LiAlH4 and aqueous workup, will yield two molecules of only a single alcohol? (A)CH3CH2CO2CH2CH3 (B)C6H5CO2C6H5 (C)C6H5CO2CH2C6H5 (D)None of these (E)All of these

64.For the following reaction, select the statement which best describes the situaton.  RCH2OH + (C5H5N)2CrO3→ (A)The alcohol is oxidized to an acid, and the Cr (VI) is reduced. (B)The alcohol is oxidized to an aldehyde, and the Cr (VI) is reduced. (C)The alcohol is reduced to an aldehyde, and the Cr (III) is oxidized (D)The alcohol is oxidized to a ketone, and the Cr (VI) is reduced. (E)The alcohol is oxidized to an acid, and the Cr (III) is reduced.

65.Which of the following alcohols gives the best yield of diakyl ether on being heated with a trace of sulfuric acid? (A)1-Pentanol (B)2-Pentanol (C)Cyclopentanol (D)2-Methyl-2-butanol (E)2-Ethyl-propanol

66.The most effective pair of reagents for the preparation of tert-butyl ethyl ether is: (A)Potassium tert-butoxide and ethyl bromide (B)Potassium tert-butoxide and ethanol (C)Sodium ethoxide and tert-butyl bromide (D)tert-Butyl alcohol and ethyl bromide (E)None of these

67.Heating a particular ether with HBr yielded a single organic product. Which of the following conclusions may be reached? (A)The reactant was a methyl ether. (B)The reactant was a symmetrical ether. (C)The reactant was a cyclic ether. (D)Both {B}and {C} are correct (E) Both {A} and {B} are correct