. 2017 Aug 22;8(10):7038–7046. doi: 10.1039/c7sc02311a

Table 1. Yields observed in the formation of bicyclic cycloadducts 5aa–5bf from (3 + 2) cycloadditions between maleimides 3a–c and imines 4a–f catalysed by an heterobimetallic complex formed by low weight salmon sperm DNA, 1a and Cu(OTf)₂.

Entry	R¹ (3)	R² (4)	5	Yield ^a (mmol × 10^–3) [%]
1	Me (3a)	Ph (4a)	5aa	10.5 ± 0.4 [21]
2	Ph (3b)	Ph (4a)	5ba	18.0 ± 0.5 [36]
3	4-MeO–C₆H₄ (3c)	Ph (4a)	5ca	10.0 ± 0.8 [20]
4	Ph (3b)	4-Me–C₆H₄ (4b)	5bb	17.9 ± 0.4 [23]
5	Ph (3b)	4-MeO–C₆H₄ (4c)	5bc	17.5 ± 0.3 [35]
6	Ph (3b)	4-F-C₆H₄ (4d)	5bd	12.5 ± 0.2 [25]
7	Ph (3b)	Cyclohexyl (4e)	5be	13.5 ± 0.4 [27]
8 ^b	Ph (3b)	2-Thyenyl (4f)	5bf	16.0 ± 0.9 [32]

^aYields of isolated pure products correspond to averaged values obtained after three experiments. The limiting reactant was the corresponding maleimide 3 (0.05 mmol).

^bStructure confirmed by X-ray diffraction analysis (ESI).⁴⁰

Table 1. Yields observed in the formation of bicyclic cycloadducts 5aa–5bf from (3 + 2) cycloadditions between maleimides 3a–c and imines 4a–f catalysed by an heterobimetallic complex formed by low weight salmon sperm DNA, 1a and Cu(OTf)2.

Table 1. Yields observed in the formation of bicyclic cycloadducts 5aa–5bf from (3 + 2) cycloadditions between maleimides 3a–c and imines 4a–f catalysed by an heterobimetallic complex formed by low weight salmon sperm DNA, 1a and Cu(OTf)₂.