Optimization studies on the reaction of perylene 1 with cysteine-S-trityl 2d using imidazole as solvent.

Entry	Reaction conditions				Product
	1	2d	Imidazole	Temperature, time
1	1 eq. (0.33 mmol)	2 eq.	17 eq.	95 °C, 3 h	3dab
2	1 eq. (0.33 mmol)	2 eq.	17 eq.	95 °C, 4 h	3dab
3	1 eq. (0.33 mmol)	2.2 eq.	17 eq.	95 °C, 3 h	3d + 4 + 5 + 6a (7.6 : 2.3 : 1.2 : 1.0)
4	1 eq. (0.33 mmol)	2.5 eq.	17 eq.	95 °C, 3 h	3d + 4 + 5 + 6a (2.5 : 1.8 : 1.0 : 1.2)
					3d, 0.24 g, 69%
5	1 eq. (0.33 mmol)	2 eq.	8 eq.	95 °C, 3 h	3d, 0.23 g, 61%
6	1 eq. (0.27 mmol)	2 eq.	17 eq.	110 °C, 3 h	3d + 4 + 5 + 6a (2.1 : 1.0 : 2.1 : 2.4)
7	1 eq. (0.77 mmol)	2 eq.	17 eq.	110 °C, 4 h	3d + 4 + 5 + 6a (2.7 : 1.0 : 2.1 : 2.5)
8	1 eq. (0.32 mmol)	2 eq.	17 eq.	110 °C, 27 h	4ac
9	1 eq. (0.31 mmol)	2 eq.	17 eq.	110 °C, 48 h	4, 0.08 g, 39%

^aBy ¹H NMR.

^bWith traces of 5 and an unknown contaminant with aromatic protons.

^cNot quantified; product with traces of 6 and broad signals in the aromatic region.