Table 5.

Calculated (B3LYP/6–31(d,p)u+1s//B3LYP/6–31G(d))^a vs observed (italics) ¹H-¹H coupling constants for 7a/8a and 7b/8b.

	7a	8a	7b	8b
	(Hz)	(Hz)	(Hz)	(Hz)
3J4β−3	8.3/7.8	10.5/11.0	6.2/6.8	10.7/11.2
3J4α−3	4.5/5.0	3.9/4.1	5.1/5.4	3.9/4.3
2J4α−4βb	15.3/15.4	15.1/15.1	15.3/15.4	15.0/15.2
5J4β−1	1.9/1.5	3.0/2.5	1.9/1.6	3.0/2.6
5J4α−1	1.2/1.2	2.0/1.9	1.8/1.4	2.1/1.9

^aWeighted average over all conformations, based on mPW1PW91/6–311+G(2d,p)//B3LYP/6–31G(d) Boltzmann distribution (298 K).

^b2J_HH values for sp³ C-H are calculated to be negative, as expected;⁵⁵ the absolute values are shown here.