A General Approach for Calculating Proton Chemical Shifts for Methyl, Methylene, and Methine Protons When There Are One or More Substituents within Three Carbons

Base Values: CH₃- Methyl=0.9 ; -CH₂- Methylene=1.2 ; -CH- Methine=1.5

Substituent Constants:

X	alpha	beta	gamma	group
R-	0.0	0.0	0.0	alkyl
R2C=CR-	0.8	0.2	0.1	alkene
RC(C-	0.9	0.3	0.1	alkyne
Ar-	1.4	0.4	0.1	aromatic
F-	3.2	0.5	0.2	fluoro
Cl-	2.2	0.5	0.2	chloro
Br-	2.1	0.7	0.2	bromo
I-	2.0	0.9	0.1	iodo
HO-	2.3	0.3	0.1	hydroxyl
RO-	2.1	0.3	0.1	ether
R2C=CRO-	2.5	0.4	0.2	vinyl ether
ArO-	2.8	0.5	0.3	aryl ether
OHC-	1.1	0.4	0.1	aldehyde
RCO-	1.2	0.3	0.0	ketone
ArCO-	1.7	0.3	0.1	aryl ketone
RCO2-	2.8	0.5	0.1	ester
ArCO2-	3.1	0.5	0.2	aromatic ester
HO2C-	1.1	0.3	0.1	carboxylate
RO2C-	1.1	0.3	0.1	carboxyl ester
ClOC-	1.8	0.4	0.1	acid chloride
H2N-	1.5	0.2	0.1	amine
RCONH-	2.1	0.3	0.1	amide-N-
H2NOC-	1.0	0.3	0.1	amide-C-
N(C-	1.1	0.4	0.2	nitrile
O2N-	3.2	0.8	0.1	nitro
HS-	1.3	0.4	0.1	sulfhydryl
RS-	1.3	0.4	0.1	sulfide
ArSO3-	2.8	0.4	0.0	sulfonate
RSO-	1.6	0.5	0.3	sulfoxide
RSO2-	1.8	0.5	0.3	sulfone

alpha= directly attached substituent
beta = once-removed substituent
gamma = twice-removed substitutent

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Examples

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