title: Unusual
abstract: All-carbon 1,3-dipoles derived from allenic esters/ketones, by catalytic interaction with triphenylphosphine, undergo an unusual [8 + 2] annelation with tropone, leading to 8-oxa-9-(ethoxycarbonyl/acylalkylidene)bicyclo[5.3.0]deca-1,3,5-trienes. Dipoles derived from allenic ketones as well as an alpha-methyl-substituted allenic ester display high reactivity and selectivity.
authors.affiliation: Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar-143 005, Punjab, India.
authors.initials: K
authors.lastname: Kumar
authors.initials: A
authors.lastname: Kapur
authors.initials: MP
authors.lastname: Ishar