Table 1.

Optimisation of the photocatalytic isomerisation of E ‐1→Z ‐1.^[a]

Entry	Catalyst	Solvent	t [h]	Irradiation wavelength [nm]	Z/E ratio[b]
1	–	cyclohexane	24	365	12:88
2	(−)‐riboflavin	MeCN	24	450	0:100
3	Ir(ppy)3	MeCN	24	450	48:52
4	benzil	MeCN	24	402	1:99
5	thioxanthone	cyclohexane	24	402	89:11[c]
6	benzophenone	MeCN	24	365	93:7[c]
7	benzophenone	cyclohexane	24	365	95:5
8	benzophenone	cyclohexane	12	365	95:5
9	benzophenone	cyclohexane	6	365	95:5
10	benzophenone	cyclohexane	2	365	95:5

[a] Reactions were performed in degassed solvent on a 0.1 mmol scale at ambient temperature under argon atmosphere, using 5 mol % of the catalyst. [b] Z/E selectivity determined by ¹H NMR spectroscopy. [c] ¹H NMR spectrum of the crude reaction mixture confirmed partial decomposition.