D
N
N
O
O
O
O
Coupling of 4-methoxyphenylboronic acid (680 mg, 1.1 equiv.) with (13) (1.20 g, 4.08 mmol)
according to procedure B (t=8 h) gave after purification by column chromatography (silica
1
gel, eluent: dichloromethane) 1.34 g (90%) of (14) as a yellow liquid. H NMR (CDCl
3
) :
8
H
6
.79 (s, 1H, H ), 7.96 (d, J=8.7 Hz, 2H, HPh’2,6), 7.62 (d, J=8.7 Hz, 2H, HPh2,6), 6.90 (m, 4H,
1
3
Ph3,5 and HPh’3,5), 4.10 (m, 4H, 2xCH
) : δ 160.9 (CPh’4), 159.5 (CPh4), 154.5 (C
Ph1 and CPh1’), 128.2 (CPh2,6 and CPh’2,6), 114.1 (CPh3,5 and CPh’3,5), 107.8 (C
2
), 3.77 (s, 3H, OCH
3
), 3.72 (s, 3H, OCH
), 138.8 (C ), 132.6 (C
), 65.2 (CH
3
). IR : 2958, 2895, 2837, 1711, 1608, 1581, 1514, 1373, 1302, 1253, 1174, 1125,
3
). C NMR
), 128.4
),
(
(
CDCl
C
3
5
), 150.8 (C
3
6
2
7
2
5
1
5.1 (OCH
073, 834, 812 cm . Anal. calcd for C H DN O (365.41) : C, 69.03; H, 5.24; N, 7.67.
-
1
2
1
19
2
4
Found: C, 68.98; H, 5.22; N, 7.63.
2
-(1-hydroxy-[4’’-methoxyphenyl]methyl)-3-(4’-methoxyphenyl)-5-(2-[4-
methoxyphenyl]-1,3-dioxolan-2-yl)pyrazine (10) and 2-(1-hydroxy-[4’’-
methoxyphenyl]methyl)-3-(2-[4-methoxyphenyl]-1,3-dioxolan-2-yl)-5-(4’-
methoxyphenyl)pyrazine (11)
O
O
OH
N
N
O
N
N
O
HO
O
O
O O
O
O
1
0
11
Metalation of (9) or (14) (200 mg, 0.55 mmol) according to procedure A with n-BuLi 1.6M
3.1 equiv., 1.06 mL), TMPH (3.1 equiv., 0.29 mL), t =30 min, θ =-78°C, followed by
addition of p-anisaldehyde (3.1 equiv., 0.2 mL) in THF (10 mL) t =60 min, θ =-78°C gave
after purification by column chromatography (silica gel, eluent : cyclohexane/ethyl acetate
(
1
1
2
2
1
(
6:4)) 192 mg (70%) of (10) and (11) as yellow liquids. (10) H NMR (CDCl
3
) : 8.75 (s, 1H,
H ), 7.50 (d, 2H, J=8.7 Hz, HPh2,6), 7.20 (d, 2H, J=8.7 Hz, HPh’2,6), 6.90 (d, 2H, J=8.7 Hz,
6
H
Ph’’2,6), 6.78 (m, 6H, HPh3,5, HPh3,5 and HPh’3,5), 5.84 (d, 1H, JCH,OH=8.7 Hz, CH), 4.55 (d, 1H,
1
J
CH,OH=8.7 Hz, OH), 4.10 (m, 4H, 2xCH
.84 (s, 1H, H ), 7.90 (d, 2H, J=8.7 Hz, HPh2,6), 7.33 (d, 2H, J=8.7 Hz, HPh’2,6), 7.05 (d, 2H,
J=8.7 Hz, HPh’’2,6), 6.92 (m, 6H, HPh3,5 Ph’3,5 and HPh’3,5), 6.25 (d, 1H, JCH,OH=8.7 Hz, CH),
2 3 3
), 3.77 (m, 9H, OCH ).(11) H NMR (CDCl ) :
8
6
H
13
4
.35 (d, 1H, JCH,OH=8.7 Hz, OH), 4.10 (m, 4H, 2xCH ), 3.77 (m, 9H, OCH ). (10 and 11) C
2 3
NMR (CDCl ) : δ 160.6-159.9 (C , C
CPh’4 ), 154.3-152.3 (Cpyr), 138.6 (C6(10) and
6(11)), 136.2-129.1 (CPh1, CPh’1 and CPh’’1), 129.9-128.1 (CPh2,6,CPh’2,6 and CPh’’2,6), 114.1 (CPh3,5,
3
Ph4
Ph’4,
C
C
Ph3,5 and CPh’3,5), 108.1 (C
7
10)
7 2 3
and C (11)), 77.2 (CH), 65.7 (CH ), 55.7 (OCH ). IR : 3449,
(
3
002, 2957, 2934, 2897, 2836, 1609, 1512, 1463, 1379, 1308, 1251, 1174, 1096, 1033, 883
-
1
,
755 cm . HRMS (IC) calculated for C29
29 2 6
H N O : 501.2025. Found : 501.2061.
3
-chloro-2-trimethylsilyl-5-(2-[4-methoxyphenyl]-1,3-dioxolan-2-yl)pyrazine (15)
S.6