N
X
C
O
N
S
Hal
Solvents
Natural
Products
P Si
C
C
C C
C
C
182
5 1 H NMR
5.3 Alkynes
1 H Chemical Shifts of Substituted Alkynes (δ in ppm)
1 H, 1 H Coupling Constants of Substituted Alkynes (J in Hz)
Substituent R
H a
–H
1.91
–CH 3
1.91
–CH 2 CH 3
1.97
–C(CH 3 ) 3
2.07
–CF 3
2.95
–CH=CH 2
3.07
–C– – – CH
2.16
–phenyl
3.07
–1-naphthyl
3.43
–F
1.74
–Cl
2.05
–Br
2.32
–I
2.34
–OCH 2 CH 3
1.48
–OCH=CH 2
2.04
–O–phenyl
2.07
–N(CH 2 CH 3 ) 2
2.30
–N(phenyl) 2
2.86
–C– – – N
2.63
Substituent R
H a
–SCH 2 CH 3
2.79
–SCH=CH 2
3.26
–S–phenyl
3.28
–S(O) 2 –n-butyl
3.95
–COCH 3
3.65
–CO–phenyl
3.48
–COOH
3.17
–COOCH 2 CH 3
2.90
–CONH 2
3.05
–Si(CH 3 ) 3
2.34
–Si(phenyl) 3
2.47
–P(CH 2 CH 3 ) 2
2.85
–P(phenyl) 2
3.22
–P(O)(CH 2 CH 3 ) 2
3.33
–P(O)(phenyl) 2
3.48
C
X
O
N
S
O
 ||
C
Si
P
H
R C C H a
H 3 C
CH 3
H
CH 3
H
CH 2 CH 3
H 3 C
CH 2 CH 3
H
H
H 3 C
H
4 J ab 2.9
| 5 J ab | 2.7
| 5 J ab | 2.5
4 J ab 2.6
5 J ac 0
3 J bc 7.4
5 J ab 0.3
6 J ac -0.1
7 J ad 0.2
4 J ab 2.0
5 J ac 1.0
6 J ad 0.6
3 J bc 10.5
4 J bd 1.6
3 J cd 6.5
a
a
a
a
a
b
b
b
b
b
b
a
c
d
c
c
d