The First Fluoride-Free Hiyama Reaction of Vinylsiloxanes
COMMUNICATIONS
1
400D-FT spectrophometer in cmÀ1. 1H NMR spectra were
recorded on a Bruker AC-300 (300 MHz)and, when speci-
fied, on a Bruker Advance-DRX-500 (500 MHz). Chemical
shifts are reported in ppm using tetramethylsilane (TMS,
0.00 ppm)as internal standard. 13C NMR spectra were re-
corded at 75 MHz with CDCl3 as the internal reference. EI-
MS were measured on a Mass Selective Detector G2579 A
from Agilent Technologies 5973N in m/z (rel. intensity in %
of base peak). The catalysts were weighed up in an electron-
ic microscale (Sartorius, XM1000P)with a precision of 1 mg.
Microwave reactions were performed with a CEM Discover
Synthesis Unit in glass vessels (10 mL)sealed with a septum
under magnetic stirring. Reaction vessels and stirring bars
were washed first with 6M NaOH solution and then with
concentrated nitric acid.
1611 (C=C), 1265 (CO) cmÀ1; H NMR (300 MHz, CDCl3,
TMS): d=7.93 (d, 2H, J=8.4 Hz, ArH), 7.49 (d, 2H, J=
8.2 Hz, ArH), 6.76 (dd, 1H, J=17.6 Hz and 10.9 Hz, ArC-
CH), 5.90 (d, 1H, J=17.6 Hz, CH-Htrans), 5.41 (d, 1H, J=
10.9 Hz, CH-Hcis), 2.59 [s, 3H, CH3(C)O]; 13C NMR: d=
197.7 (C=O), 142.2 (ArC), 136.4 (ArC), 136.0 (CH), 128.8,
128.6 (ArCH), 126.4 (ArCH), 116.8 (CH2), 26.7 (CH3) ; MS
(EI): m/z (% rel. int.)=146 (42)[M +], 131 (100), 103 (64).
(E)-1-Phenyl-1,3-butadiene:[21] Oil; Rf =0.64 (pentane/di-
ethyl ether, 10:1); IR (film): n=3033 (C=CH), 1678 (C=C),
1601 (CH=CH2), 1421 (C-C) cmÀ1 1H NMR (300 MHz,
;
CDCl3, TMS): d=7.4–7.21 (m, 5H, ArH), 7.38 (d, 1H, J=
16.8 Hz, Ar-CH-), 6.83 (dd, 1H, J=16.05 and 10.7 Hz, CH),
6.58 (ddd, 1H, J=16.8, 10.3 and 10.1 Hz, CH), 5.35 (d, 1H,
J=16.5 Hz, CH-Htrans), 5.18 (d, 1H, J=10.3 Hz, CH-Hcis);
13C NMR: d=137.3 (CH); 133.0 (ArC), 129.7 (CH), 128.7
(ArCH), 127.7 (ArCH), 126.5 (ArCH), 117.7 (CH2) ; MS
(EI): m/z (% rel. int.)=130 (66)[M +], 129 (100), 115 (36).
1-Vinylnaphthalene:[21] Yellow solid; mp 64–668C; Rf =
0.52 (hexane); IR (KBr): n=3054 (C=CH), 1634, 1596 (C=
Typical Experimental Procedure for Hiyama
Coupling of Aromatic and Vinyl Bromides and
Chlorides with Vinylsiloxanes under Microwave
Irradiation
C)cm À1; H NMR (300 MHz, CDCl3, TMS): d=8.11 (d, 1H,
1
J=8.7 Hz, ArH), 7.84 (d, 1H, J=7.17 Hz, ArH), 7.81 (d,
1H, J=8.3 Hz, ArH), 7.62 (d, 1H, 6.9 Hz, 1H, ArH), 7.52–
7.41 (m, 4H, ArH), 5.81 (d, 1H, J=17.3 Hz, CH-Htrans), 5.48
(d, 1H, J=10.9 Hz, CH-Hcis); 13C NMR: d=135.7 (ArC),
134.5 (CH), 133.7 (ArC), 131.2 (ArC), 128.6 (ArCH), 128.2
(ArCH), 126.1 (ArCH), 125.8 (ArCH), 123.8 (ArCH), 123.7
(ArCH), 117.2 (CH2) ; MS (EI) :m/z (% rel. int.)=154 (76)
[M+], 153 (100), 152 (56), 76 (59).
A glass tube (10 mL)was charged with the organic halide
(0.5 mmol), vinylsiloxane (1 mmol), TBAB (0.5 to 1 mmol,
see Tables 1 and 2), Pd salt or palladacycle (see Tables 1
and 2), and H2O (1 mL). Then an aqueous 50% NaOH solu-
tion (0.05 mL, 1.25 mmol)was added dropwise and the tube
was sealed with a septum and heated at 1208C (40–45 W, 4–
5 bar)during the time indicated in Tables 1–3 with air
stream cooling. After the reaction was stopped, the reaction
mixture was cooled to room temperature and extracted with
ether (510 mL). Then the organic phases were washed suc-
cessively with 2M NaOH (220 mL), 2M HCl (20 mL), and
brine (220 mL). The ethereal layer was dried (MgSO4)
and evaporated (15 mm Hg). The subsequent residue was
purified by flash chromatography on silica gel to give pure
alkenes.
2-Vinyl-6-methoxynaphthalene:[21] White solid; mp 91–
938C; Rf =0.60 (hexane/diethyl ether, 10:1); IR (KBr): n=
3054 (C=CH), 2838 (OMe), 1633, 1597 (C=C), 1482 (C-C),
À1
1258 (C-O)cm
;
1H NMR (300 MHz, CDCl3, TMS): d=
7.72–7.68 (m, 3H, ArH), 7.62 (d, 1H, J=8.5 Hz, ArH), 7.14
(d, 2H, J=8.13 Hz, ArH), 6.89 (dd, 1H, J=17.6 and
10.9 Hz, CH), 5.85 (d, 1H, J=17.6 Hz, CH-Htrans), 5.29 (d,
1H, J=10.9 Hz, CH-Hcis); 13C NMR: d=157.7 (ArC), 136.9
(CH), 134.2 (ArC), 132.9 (ArC), 129.5 (ArCH), 128.8
(ArC), 126.9 (ArCH), 126.1 (ArCH), 123.7 (ArCH), 118.9
(ArCH), 113.0 (CH2), 105.7 (ArCH), 55.2 (OCH3) ; MS (EI) :
m/z (% rel. int.)=184 (100)[M +], 169 (17), 141 (50), 115
(19).
Typical Experimental Procedure for Hiyama
Coupling of Aromatic and Vinyl Bromides with
Vinylsiloxanes under Thermal Conditions
A
mixture of organic halide (1 mmol), vinylsiloxane
(2 mmol), TBAB (0.5 to 1 mmol, see Tables 1 and 2) and
Pd(OAc)2 or palladacycle 1 (see Tables 1 and 2)and H O
4’-Vinylbenzophenone:[23] White solid; mp 50–528C; Rf =
0.45 (hexane/EtOAc, 10:1); IR (KBr): n=3090 (C=CH),
ACHTREUNG
2
1655 (C=O), 1612 (C=C), 1265 (C-O) cmÀ1
;
1H NMR
(2 mL)in a 15 mL Ace tube was stirred during 5 min. Then
an aqueous 50% NaOH solution (0.1 mL, 2.5 mmol)was
added dropwise and the reaction mixture was heated at
1208C during the time indicated in Table 2. The reaction
mixture was cooled to room temperature followed by ex-
tractive work up as above.
(300 MHz, CDCl3, TMS): d=7.77 (dd, 4H, J=8.3 and
6.39 Hz, ArH), 7.59–7.43 (m, 5H, ArH), 6.81 (dd, 1H, 17.4
and 10.7 Hz, CH), 5.91 (d, 1H, J=17.4 Hz, CH-Htrans), 5.41
(d, 1H, J=10.7 Hz, CH-Hcis); 13C NMR: d=196.2 (C=O),
141.5 (ArC), 138.9 (ArC), 137.7 (ArC), 137.2 (CH), 136.7
(ArCH), 136.0 (ArCH), 132.7 (ArCH), 130.1 (ArCH), 126.1
(ArCH), 116.6 (CH2) ; MS (EI) :m/z (% rel. int.)=209 (13)
4’-Methoxystyrene:[21] Oil; Rf =0.63 (hexane/EtOAc,
10:1); IR (film): n=3072 (C=CH), 2929 (CH), 2829 (OMe),
+
[M+ +1], 208 (80)[M ], 131 (100), 105 (29), 77 (43).
1
1689, 1601 (C=C)cm À1; H NMR (400 MHz, CDCl3, TMS):
A
d=7.35 (d, 2H, J=8.6 Hz, ArH), 6.86 (d, 2H, J=8.6 Hz,
ArH), 6.69 (dd, 1H, J=17.6 Hz and 10.9 Hz, ArC-CH), 5.62
(dd, 1H, J=17.6 and 0.8 Hz, CH-Htrans), 5.13 (dd, 1H, J=
10.9 and 0.8 Hz, CH-Hcis), 3.79 (s, 3H, CH3O); 13C NMR:
d=159.5 (ArC-O), 136.4 (CH), 130.6 (ArC), 127.5 (ArCH),
114.0 (ArCH), 111.6 (CH2), 55.4 (CH3O); MS (EI): m/z (%
rel. int.)=135 (M+ +1, 9), 134 (100) [M+], 119 (61), 91 (65).
4’-Vinylacetophenone:[22] Oil; Rf =0.45 (hexane/EtOAc,
10:1); IR (film): n=3029 (C=CH), 2926 (CH), 1683 (C=O),
152–1538C; Rf =0.25 (pentane); IR (KBr): n=3011 (C=
CH), 1604, 1568 (C=C), 1446 (C-C) cmÀ1 1H NMR
;
(CDCl3): d=7.45 (d, 4H, J=8.3 Hz, ArH), 7.35–7.31 (m,
4H, ArH), 7.23–7.21 (m, 2H, ArH), 6.99 (dd, 2H, J=10.4
and 14.6 Hz, CH), 6.71 (dd, 2H, J=14.6 and 9.1 Hz, CH);
13C NMR (CDCl3): d=137.5 (ArC), 132.9 (CH), 129.3, 128.7
(ArCH), 127.7 (CH), 126.5 (ArCH); MS (EI): m/z (% rel.
int.)=206 (100)[M +], 205 (40), 191 (36), 128 (31), 91 (32).
Adv. Synth. Catal. 2006, 348, 2085 – 2091
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2089