Table 2.

Computational Data for Cycloaddition Products 10b and 11b.^a

Compound	State	Energy TD-DFT [eV]b	Oscillator Strength	Exp. Absorption [eV]c	Exp. εabs [M−1cm−1]c
10b	S1 (n-π*)	3.34	0.013	3.26	800
	S2 (n-π*)	3.63	0.091	3.57	1,700
	S3 (π-π*)	4.23	0.016	3.99	540
	S4 (π-π*)	4.34	0.581	4.16	8,300
11b	S1 (π-π*)	3.66	0.205	3.42	10,600
	S2 (n −π*)	4.40	0.086	n.d.	n.d.
	S3 (n-π*)	4.42	0.068	n.d.	n.d.
	S4 (π-π*)	4.65	0.025	n.d.	n.d.

^aCalculated at the TD-CAM-B3LYP/6–31+G(d)//B3LYP/6–31G(d) level of theory.

^bVertical excitation energy

^cDetermined based on Gaussian fitting as illustrated in Figure 3.