. 2025 Jul 14;15(30):24544–24556. doi: 10.1039/d5ra03698d

Table 1. Photochemical [2 + 2] cycloadditions of diesters 6 and synthesis of cyclobutane diesters 7.


Entry	Cycloaddition product	Yield of 15 (%)^a		Final product	Yield of 7 (%)^a
Entry	Cycloaddition product	Powder	solution^b	Final product	Yield of 7 (%)^a
1		88	88 (dr = 97 : 3)^c		75
2		11	64 (dr = 93 : 7)^c		91
3		35	85 (dr = 96 : 4)^c		87

Yields refer to isolated product yields after purification by column chromatography.

Photochemical solution reactions were conducted in CHCl₃ in quartz test tubes.

Diastereomeric ratio (dr) values of the crude reaction mixtures were determined by ¹H NMR spectroscopy. The products were obtained as single diastereomers after purification.