4.22 Name the following alkynes, and predict the products of their reaction with (i) H2 in the presence of a Lindlar catalyst and (ii) H30* in the pres- ence of HgSO4: (a) (b)

A compound with formula C8H12 reacts with 2 molar equiv of H₂ to yield a cycloalkane. By treatment of this compound with acidic KMnO4, a dicarboxylic acid, HOOCCH2CH2COOH is obtained. What is the structure of this compound? (A) (B) (C) (D)

2. (a) Reaction of an alkene with ozone followed by an oxidative workup gives the product shown. What is the structure of alkene A? A (b) Compounds B and C both have the formula C10H16. Hydrogenation of either compound over Pt gives the same product, cis-1-isopropyl-4-methylcyclohexane. Ozonolysis with reductive workup fragments the two compounds differently, as shown below. What are the structures of C B and C? (CHCl3, chloroform, is the solvent.) B 1) 03, CHCI 3 2) (CH3)2S 1) 03, CHC13 2) (CH3)2S H O 1) 03 2) H₂O2, H₂O H3C- H O CH3 3. (a) Draw the structures of all enols that would spontaneously form this ketone, including stereoisomers. + + I HO₂C H + La CH3CH₂-C-CH(CH3)2 O= (b) Would alkyne hydration be a good preparative method for this compound? If so, give the reaction. If not, explain why.

Arrange the alkenes in each set in order of increasing rate of reaction with HI and explain the basis for your ranking. Draw the structural formula of the major product formed in each case. (a) and (b) H3CH₂CHC=CH₂ and (H3C) 2C=CHCH3

4.2 10 Give the reaction mechanism showing all possible products for the following reactions: (a) Reaction of 1-propene with hydrogen bromide, HBr (g) (b) Reaction of ethene with bromine, Br₂ (1)

(a) Account for the following :(i) Electrophilic substitution reactions in haloarenes occur slowly.(ii) Haloalkanes, though polar, are insoluble in water.(b) Arrange the following compounds in increasing order of reactivity towards SN2 displacement:2-Bromo-2-Methylbutane, 1-Bromopentane, 2-Bromopentane

and (ii) KMnO4 in aqueous NaOH: 1. Name the following alkenes, and predict the products of their reaction with (i) KMnO4 in aqueous acid (a) (b) 2. Draw structures corresponding to the following IUPAC names: (a) 3-Ethylhept-1-yne (b) 3,5-Dimethylhex-4-en-1-yne (c) Hepta-1,5-diyne (d) 1-Methylcyclopenta-1,3-diene (1) 3. Draw and name all the possible pentyne isomers, C5H8. H H Ç-H [ Pent-1-yne] (2) 4. Predict the products of the following ring is inert to all the indicated reagents.) 4 H 4- (3) 4-C C = C-4 [3-methylbut -1-4 [Pent-2-yhdioselectivity where relevant. (The aromatic CH=CH2 Styrene (a) Styrene+H2 Pd, ? (c) Styrene+HBr ? (b) Styrene+Br2 → ? (d) Styrene+KMnO4 NaOH, H2O ? 5. Suggest structures for alkenes that give the following reaction products. There may be more than one answer for some cases. HyPd catalyst (a) ? Br₂ in CH2Cl2 (b) ? HBr (c) ? 2-Methylhexane 2,3-Dibromo-5-methylhexane 2-Bromo-3-methylheptane CH3 HO OH CH3CHCH2CHCHCH2CH3 KMnO4OH (d) ? H₂O

11:43 Q1. (a) (c) (d) (b) Two stereoisomers of but-2-ene are formed when 2-bromobutane reacts with ethanolic potassium hydroxide. (i) Explain what is meant by the term stereoisomers. Library Name and outline a mechanism for the reaction of 2-bromo-2-methylpropane with ethanolic potassium hydroxide to form the alkene 2-methylpropene, (CH3)2C=CH₂ Name of mechanism Mechanism (ii) Draw the structures and give the names of the two stereoisomers of but-2-ene. Stereoisomer 1 Name (iii) Name this type of stereoisomerism. Select Name Stereoisomer 2 When 2-bromo-2-methylpropane reacts with aqueous potassium hydroxide, 2-methylpropan-2-ol is formed as shown by the following equation. CH3 H₂C-C-CH3 + KOH Br Page 2 of 14 CH3 H3C-C-CH3 + KBr ОН State the role of the hydroxide ions in this reaction. Write an equation for the reaction that occurs when CH3CH₂CH₂CH₂Br reacts with an excess of ammonia. Name the organic product of this reaction. Equation Name of product 9,284 Photos, 1,166 Videos For You…

Assign E or Z stereochemistry to each of the following alkenes, and convert each drawing into a skeletal structure (red = 0, yellow-green = Cl). (a) (b)

Provide the expected product for the reaction of each of the following alkenes with (i) HBr and (ii) HBr, H₂O₂. 3 (b) (c) (d) (e)