ABSTRACT
The trifluoromethyl group is larger than the methyl group but significantly smaller than the trichloromethyl group (Table 5. l).3 Perhaps surprisingly the replacement of a CH, group by CF, has little or no effect on the bond length between the group and the aromatic nucleus. The low steric impact of CF, is particularly important in terms of pharmacological properties, since the replacement of CH, by CF, should result in minimal disruption to an enzyme-substrate complex.
