Table 3. Photophysical Properties of Compound 4c.

entry	solvent	absorptiona λmax,abs (nm)	emissiona λmax,emi (nm)	molar extinction coefficient × 104 (ε) π–π*	Stoke’s shift Δν̅ (cm–1)b	quantum yield (Φf)c
1	CH3CN	228, 263	414	5.00985	19 705	0.3681
2	MeOH	230, 264	436	5.12955	20 542	0.3195
3	THF	247, 317	409	1.67091	16 035	0.1063
4	dioxane	271, 317	408	0.97554	12 390	0.2146
5	toluene	287, 319	407	0.56647	10 273	0.2270

^aRecorded at 298 K.

^bStoke’s shift = λ_max,abs – λ_max,emi [cm ^–1].

^cDetermined with anthracene as a standard Φ_f = 0.27 at an excitation wavelength of 246 nm.