. Author manuscript; available in PMC: 2014 Nov 15.

Published in final edited form as: J Org Chem. 2013 Oct 28;78(22):10.1021/jo402010b. doi: 10.1021/jo402010b

Table 1.

Optimization of the Photochemical Benzannulation

entry	diazo ketone (equiv)	solvent	irradiation^a time (h)	yield (%)^b
1	1.0	CH₂Cl₂	8	48
2	2.5	CH₂Cl₂	5.5	67
3	1.5	CH₂Cl₂	4.5	65^c
4	2.5	CH₂Cl₂	10	85^c
5	2.5	ClCH₂CH₂Cl	9	73^c^d

Irradiation with a 450 W medium-pressure mercury lamp (220-600 nm).

Isolated yields of products purified by column chromatography.

A solution of diazo ketone (0.4 M) was added to the ynamide solution via syringe pump (ca. 0.009 mL/min).

Heated in DCE (reflux, 24 h) after irradiation.