Table 1. Twist sense control in p-imine o-phenylenes.

Compound	de a	Twist sense b
(R)-oP6(p-tBu)	40%	M
(S)-oP6(p-tBu)	40%	P
(R)-oP6(p-iPr)	24%	M
(S)-oP6(p-Et)	8%	P
(R)-oP6(p-Cy)	14%	M
(S)-oP6(p-Bo)	28%	P
(S)-oP6(p-Ph)	8%	n.d.
(S)-oP6(p-Np)	10%	n.d.

^aDetermined from ¹H NMR deconvolution at 273 K (CDCl₃). Only the perfectly folded state was considered.

^bAssigned from CD spectroscopy (sign of Cotton effect at 260 nm).