Spectral Properties of Dyes with Interfragmental Charge Transfer: Solvatochromism and Solvatofluorochromism of 2-(3-Coumaroyl)-benzopyrylium Perchlorates

Table 1

Conditions for the synthesis of CBP derivatives.

	Refluxing duration, min	Solvent for the initiation of precipitation	Solvents used for recrystallisation	Yield, %
I	10–15	—	Ethanol	77
II	20	—	Ethanol	73
III	20	—	Ethanol	72
IV	30	—	Concentrated acetic acid	66
V	20	—	Isopropanol	70
VI	20	Isopropanol	Isopropanol-acetonitrile (4 : 1 v/v)	64
VII	20	Isopropanol	Acetonitrile	57