214 ALKYNES 9.17Three isomers have unbranched carbon chains: CH2CH2CH2CH2C≡CHCH3CH2CH2C≡CCH3CH2CHC≡CCH2CH3 1-Hexyne 2-Hexyne Next consider all the alkynes with a single methyl branch CH3CHCH2C≡CHCH3CH2CHC≡ CH CH3CHO≡CCH2 H3 4-Methyl-l-pentyne 3-Methyl-l-pentyne 4-Methyl-2-pentyne One isomer has two methyl branches. None is possible with an ethyl branch CH2CC≡CH 3.3-Dimethyl-1-butyne 9. 18(a) CH CH, CHaCECH is 1-pentyne (b) CH CH,CECCH, is 2-pentyne (c) CH_ C=CCHCHCH3 is 4, 5-dimethyl-2-hexyne H3C CH (d) H, CH,CH, CECH is 5-cyclopropyl-l-pentyne CECCHos is cyclotridecyne (e) (f) CHCH, CH,CH, CHCH,CH, CH,CH, CH3 is 4-butyl-2-nonyne (Parent chain must contain the triple bond. H3 (g) CH CC=CCCH3 is 2, 2,5,5-tetramethyl-3-hexyne CH3 CH 9. 19 (a) 1-Octyne is HCECCH, CH,CH,CH, CH, CH (b) 2-Octyne is CH C=CCH,CH,CH,CH,CH (c) 3-Octyne is CH CH,C=CCH, CH, CH, CH3 (d) 4-Octyne is CH_CH,CH,C=CCH, CH,CH3 (e) 2, 5-Dimethyl-3-hexyne is CH CHCECCHCH () 4-Ethyl-1-hexyne is CH3 CH2CHCH,CECH CHCH Back Forward Main Menu TOC Study Guide Toc Student OLC MHHE Website9.17 Three isomers have unbranched carbon chains: Next consider all the alkynes with a single methyl branch: One isomer has two methyl branches. None is possible with an ethyl branch. 9.18 (a) (b) (c) (d) (e) ( f ) (g) 9.19 (a) (b) (c) (d) (e) ( f ) 4-Ethyl-1-hexyne is CH3CH2CHCH2C CH2CH3 CH 2,5-Dimethyl-3-hexyne is CH3CHC CH3 CCHCH3 CH3 4-Octyne is CH3CH2CH2C CCH2CH2CH3 3-Octyne is CH3CH2C CCH2CH2CH2CH3 2-Octyne is CH3C CCH2CH2CH2CH2CH3 1-Octyne is HC CCH2CH2CH2CH2CH2CH3 CH3CC CH3 CH3 CCCH3 is 2,2,5,5-tetramethyl-3-hexyne CH3 CH3 1 2 46 3 5 CH3CH2CH2CH2CHCH2CH2CH2CH2CH3 is 4-butyl-2-nonyne C CCH3 45 6 7 8 9 3 21 (Parent chain must contain the triple bond.) CCH2 2 3 CH2C 13 1 is cyclotridecyne CH2CH2CH2C CH is 5-cyclopropyl-1-pentyne 543 2 1 CH3C H3C CCHCHCH3 is 4,5-dimethyl-2-hexyne CH3 1 2 3 4 5 6 CH3CH2C CCH3 is 2-pentyne 5 4 3 21 CH3CH2CH2C CH is 1-pentyne 543 2 1 CH3CC CH3 CH3 CH 3,3-Dimethyl-1-butyne CH3CHC CH3 CCH3 4-Methyl-2-pentyne CH3CH2CHC CH3 CH 3-Methyl-1-pentyne CH3CHCH2C CH3 CH 4-Methyl-1-pentyne CH3CH2CH2CH2C CH CH3CH2CH2C CCH3 CH3CH2C CCH2CH3 1-Hexyne 2-Hexyne 3-Hexyne 214 ALKYNES Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website