Table 1. β-KIEs Measured between 5 and 35 °C for Deuterated H₂Fs^a.

	R1	R2	R3	R4	β-KIEav
[7-2H] H2F	H	H	H/D (racemic)		0.96 ± 0.01
[9-2H] H2F	H/D (racemic)		H	H	0.96 ± 0.01
(R)-[9-2H] H2F	D	H	H	H	0.960 ± 0.009
(S)-[9-2H] H2F	H	D	H	H	0.980 ± 0.005
[9,9-2H2] H2F	D	D	H	H	0.952 ± 0.006
[7,9-2H2] H2F	H/D (racemic)		H/D (racemic)		0.95 ± 0.01
[7,9,9-2H3] H2F	D	D	H/D (racemic)		0.924 ± 0.006

^aEach value represents the average of the β-KIEs measured at 5, 10, 15, 20, 25, 30, and 35 °C for each compound (Table S1). Errors are intended as standard deviations of the mean values.