Table 3.

Activation parameters for enantiomerization of [n]helicenes (n=3 and 6) substituted at the inner, middle, and outer helix.

	Position of methyl group(s)	ΔH ≠ [kcal mol−1]	ΔS ≠ [cal K−1 mol−1]	ΔG ≠ [kcal mol−1] at (T [K])
	1	38.5	−9.8	43.0 (542)[a]
	1,14	–	–	43.1 (543)[a]
	1,16	–	–	43.8 (543)[a]
	1,3,14,16	37.7	−12.9	43.8 (543)[a]
	2,15	–	–	40.6 (513)[a]
	4,13	–	–	36.3 (469)[a]
	4,5	13.9	−7.9	16.1 (298)[b]
	3,4,5,6	21.9	−3.9	23.1 (298)[b]

[a] Gibbs activation energy recalculated by using the equation ΔG ^≠(T)=−RT ln(k _e h/κk _B T) with κ=0.5, see ref. [47]. [b] Originally reported values, the recalculation was not possible because values of the rate constant were not available, see ref. [33].