CONJUGATION IN ALKADIENES AND ALLYLIC SYSTEMS 237 10.18 (a) H,C=CH(CH,)CH=CH2 (b)(CH ),C=CC=C(CH,)2 2,3, 4.5-Tetramethyl-2, 4-hexadiene (c)CH2=CH-CH—CH=CH CHECH CH3 3-lsopropenyl-1, 4-cyclohexadiene HH (1Z3E.5Z)-1. 6-Dichloro-1 3,5-hexatriene ()HC=C=CHCH=CHCH3 1.2. 4-Hexatriene HC、 CHECH, CHCH CH, CH3 (E)3-Ethyl-4-methyl-1, 3-hexadiene 10.19 (a) Since the product is 2, 3-dimethylbutane we know that the carbon skeleton of the starting ma ince 2,3-dimethylbutane is CH and the starting material is C6Hio, two molecules of H must have been taken up and the starting material must have two double bonds. The starting material can only be 2, 3-dimethy l-1,3-butadiene. H2C=C—C=CH2+2H2 CH3), CHCH(CH CH, CH Back Forward Main Menu TOC Study Guide Toc Student OLC MHHE Website10.18 (a) (b) (c) (d) (e) ( f ) (g) (h) 10.19 (a) Since the product is 2,3-dimethylbutane we know that the carbon skeleton of the starting ma￾terial must be Since 2,3-dimethylbutane is C6H14 and the starting material is C6H10, two molecules of H2 must have been taken up and the starting material must have two double bonds. The starting material can only be 2,3-dimethyl-1,3-butadiene. H2C C CH3 C CH2 CH3 2H2 (CH3)2CHCH(CH3)2 Pt C C C C C C (E)-3-Ethyl-4-methyl-1,3-hexadiene C C CH3CH2 H3C CH2CH3 CH CH2 (1E,5E,9E)-1,5,9-Cyclododecatriene H2C CHCH C CHCH3 1,2,4-Hexatriene H H H Cl H Cl H H (1Z,3E,5Z)-1,6-Dichloro-1,3,5-hexatriene CH2 CH3 H 3-Isopropenyl-1,4-cyclohexadiene CH2 CH CH CH CH2 CH CH2 3-Vinyl-1,4-pentadiene (CH3)2C C(CH3)2 CH3 CH3 CC 2,3,4,5-Tetramethyl-2,4-hexadiene H2C CH CH(CH2 2 )5CH 1,8-Nonadiene CONJUGATION IN ALKADIENES AND ALLYLIC SYSTEMS 237 Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website