2292
M. R. H. Mahran et al.
[t, 3J8,7 = 7.3 Hz, 3H, 8-H, Z-isomer]; 1.32–1.46 [m, 4H, 7-H, E- and Z-
isomers]; 1.49 [d, 3J1,2 = 8.4 Hz, 2H, 1-H, E-isomer]; 1.63 [d, 3J1,2 = 8.9
Hz, 2H, 1-H, Z-isomer]; 1.98–2.11 [m, 4H, 6-H, E- and Z-isomers]; 5.35
[dt, 3J2,1 = 8.9 Hz, 3J2,3 = 10.8 Hz, 1H, 2-H, Z-isomer]; 5.48 [dt, 3J2,1
=
3
3
8.4 Hz, J2,3 = 13.6 Hz, 1H, 2-H, E-isomer]; 5.56 [dt, J5,4 = 14.6 Hz,
3J5,6 = 7.6 Hz, 1H, 5-H, E-isomer]; 5.60 [dt, 3J5,4 = 15.0 Hz, 3J5,6 = 7.0
3
3
Hz, 1H, 5-H, Z-isomer]; 5.87 [dd, J3,2 = 13.6 Hz, J3,4 = 10.1 Hz, 1H,
3
3-H, E-isomer]; 5.89 [t, J3,2 = 10.8 Hz, 1H, 3-H, Z-isomer); 5.99 [dd,
3J4,3 = 10.1 Hz, J4,5 = 14.6 Hz, 1H, 4-H, E-isomer); 6.24 [dd, J4,3
=
3
3
11.0 Hz, 3J4,5 = 15.0 Hz, 1H, 4-H, Z-isomer).
13C NMR (CDCl3,δ): −1.9 [Si(CH3)3, E-isomer]; -1.7 [Si(CH3)3, Z-
isomer]; 12.7 [C8, E-isomer]; 13.7 [C8, Z-isomer]; 19.3 [C1, Z-isomer];
19.8 (C7, E-isomer); 22.7 (C7, Z-isomer); 23.4 (C1, E-isomer); 34.8 [C6,
E-isomer); 35.0 (C6, Z-isomer); 126.0, 126.2, 126.5, 128.8, 129.3, 130.3,
130.8, 133.0 (C2, C3, C4, C5, E− and Z-isomers).
GC/EIMS [70 eV, m/z (relative abundance %)], E-isomer: 182 (1.8)
[M]+, 109 (< 1) [M − SiMe3]+, 108 (2.4) [M – (SiMe3 + H)]+, 73 (100)
[SiMe3]+; Z-isomer: 182 (2.6) [M]+, 109 (<1) [M − SiMe3]+, 108 (2.6)
[M − (SiMe3+ H]+, 73 (100) [SiMe3]+.
1-(Trimethylsilylmethyl)-2-methyl-4-phenyl-1,3-butadiene (7e).
White waxy solid (2.90 g, 62.9%; E:Z 89:11), m.p. 32–34◦C. Calcd.
for C15H22Si ( 230.42): C, 78.19; H, 9.62. Found: C, 78.18; H, 9.77. IR
(CDCl3, cm−1): 3060 (w), 3040 (w) ( ν C H arom); 3010 (m, ν C H
alkene); 2940 (s, νas C H satd.); 2870 (m, νs C H satd.); 1620 (m, ν C C
alkene); 1590 (m), 1485 (m) ( ν C C arom); 1405 (w, δas CH3 on Si); 1240
(s, δs CH3 on Si); 945 (s, δ CH CH trans out-of-plane def.); 840 (vs), 765
(w) (CH3 on Si rocking vib.); 650 (w, νas Si C); 595 (w, νs Si C);
1H NMR (CDCl3, δ): 0.00 [s, 9H, Si(CH3)3, E-isomer]; 0.01 [s, 9H,
3
Si(CH3)3, Z-isomer]; 1.63 [d, J1,2=9.0 Hz, 2H, 1-H, E-isomer]; 1.69
3
4
[d, J1,2 = 9.8 Hz, 2H, 1-H, Z-isomer]; 1.78 [d, J6,2 = 0.6 Hz, 3H,
4
6-H, E-isomer]; 1.91 [d, J6,2 = 1.1 Hz, 3H, 6-H, Z-isomer]; 5.49 [t,
3J2,1 = 9.8 Hz, 1H, 2-H, Z-isomer]; 5.69 [t, J2,1 = 9.0 Hz, 1H, 2-H,
3
E-isomer]; 6.33 [d, 3J5,4 = 16.0 Hz, 1H, 5-H, E-isomer]; 6.46 [d, 3J5,4
=
16.0 Hz, 1H, 5-H, Z-isomer]; 6.79 [d, 3J4,5 = 16.0 Hz, 1H, 4-H, E-isomer];
7.08-7.37 [m, 11H, 4-H of Z-isomer and aromatic protons of E- and
Z-isomers].
13C NMR (CDCl3, δ): –1.5 [Si(CH3)3, E- and Z-isomers); 12.4 [C10, E-
isomer); 19.4 [C1, Z-isomer]; 20.4 [C10, Z-isomer]; 20.6 (C1, E-isomer);
124.0, 126.1, 126.4, 126.6, 127.0, 128.6, 131.3, 134.6 [C2, C4, C5, C7,
C8, C9, E- and Z-isomers]; 129.8 (C3, Z-isomer); 131.7 [C3, E-isomer];
138.4 (C6, E- and Z-isomers).