Investigations on photochemistry of o-allyloxy-/crotyloxyacetophenones: formation of unexpected intramolecular arene–olefin addition products on n–π∗ excitation of ketones
作者:Rajinder Singh、M.P.S. Ishar
DOI:10.1016/s0040-4020(02)00868-2
日期:2002.9
(8a,b), besides some highly unexpected intramolecular arene-olefin additionproducts (14–16); formation of these intramolecular arene–olefin additionproducts is quenched in the presence of 0.1 mol equiv. of triethylamine. With increasing molar ratios of triethylamine, in acetonitrile solvent, the formation of 7, 8 is also suppressed with increased formation of products (9–13) derived from photoreduction
Intramolecular Ketone-Olefin Radical Cyclization with Low-Valent Titanium Reagent: Synthesis of Benzopyrans
作者:Sandip K. Nayak、Suchitra Bhatt、Kshama Roy
DOI:10.1080/00397910903340710
日期:2010.9.20
A novel protocol for intramolecular ketyl-olefin radicalcyclization with low-valent titanium reagent is outlined. It allows the formation of the benzopyran nucleus from ortho-allyloxy propiophenones as the sole product in moderate yields via intramolecular radicalcyclization.