N
X
C
O
N
S
Hal
Solvents
Natural
Products
P Si
C
C
C C
C
C
76
4 13 C NMR
76
4 13 C NMR
13 C Chemical Shifts of Methyl Groups (δ in ppm)
Substituent R
δ CH 3 –R
–H
-2.3
–CH 3
7.3
–CH 2 CH 3
15.4
–CH(CH 3 ) 2
24.1
–C(CH 3 ) 3
31.3
–(CH 2 ) 6 CH 3
14.1
–CH 2 –phenyl
15.7
–CH 2 F
15.8
–CH 2 Cl
18.7
–CH 2 Br
19.1
–CH 2 I
20.4
–CHCl 2
31.6
–CHBr 2
31.8
–CCl 3
46.3
–CBr 3
49.4
–CH 2 OH
18.2
–CH 2 OCH 3
14.7
–CH 2 OCH 2 CH 3
15.4
–CH 2 OCH=CH 2
14.6
–CH 2 O–phenyl
14.9
–CH 2 OCOCH 3
14.4
–CH 2 NH 2
19.0
–CH 2 NHCH 3
14.3
–CH 2 N(CH 3 ) 2
12.8
–CH 2 NO 2
12.3
–CH 2 SH
19.7
–CH 2 S(O) 2 CH 3
6.7
–CH 2 S(O) 2 OH
8.0
–CH 2 CHO
5.2
–CH 2 COCH 3
7.0
–CH 2 COOH
9.6
–cyclopentyl
20.5
–cyclohexyl
23.1
–CH=CH 2
18.7
–C– – – CH
3.7
–phenyl
21.4
–1-naphthyl
19.1
–2-naphthyl
21.5
Substituent R
δ CH 3 –R
–2-pyridyl
24.2
–3-pyridyl
18.0
–4-pyridyl
20.6
–2-furyl
13.7
–2-thienyl
14.7
–2-pyrrolyl
11.8
–2-indolyl
13.4
–3-indolyl
9.8
–4-indolyl
21.6
–5-indolyl
21.5
–6-indolyl
21.7
–7-indolyl
16.6
–F
71.6
–Cl
25.6
–Br
9.6
–I
-24.0
–OH
50.2
–OCH 3
60.9
–OCH 2 CH 3
57.6
–OCH(CH 3 ) 2
54.9
–OC(CH 3 ) 3
49.4
–OCH 2 CH=CH 2
57.4
–O–cyclohexyl
55.1
–OCH=CH 2
52.5
–O–phenyl
54.8
–OCOCH 3
51.5
–OCO–cyclohexyl
51.2
–OCOCH=CH 2
51.5
–OCO–phenyl
51.8
–OCOOCH 3
54.9
–OS(O) 2 –4-tolyl
56.3
–OS(O) 2 OCH 3
59.1
–OP(OCH 3 ) 2
48.8
–NH 2
28.3
–NH 3
+
26.5
–NHCH 3
38.2
–NH–cyclohexyl
33.5
–NH–phenyl
30.2
C
X
O
N
C