Table 2

Steric substituent parameters for propranolol analogs

Compound	Substituent	E_s–Taft^2-a	Charton van der Waals radiusr_v^2-b
P	CH₃	−1.24	1.72 Å
FP	CH₂F	−1.48	1.82 Å
iPrMe	CH(CH₃)₂	−1.71	1.96 Å
DFP	CHF₂	−1.91	1.88 Å
TFP	CF₃	−2.40	2.01 Å
tBuMe	C(CH₃)₃	−2.78	2.44 Å

↵2-a Hansch et al., 1995.
↵2-b r_v = Charton υ value (H = 0) + 1.20 Å (van der Waals radius of H atom) (Charton, 1975).