title: Spiro annulation of cage polycycles via Grignard reaction and ring-closing metathesis as key steps.
abstract: A simple synthetic strategy to C 2-symmetric bis-spiro-pyrano cage compound 7 involving ring-closing metathesis is reported. The hexacyclic dione 10 was prepared from simple and readily available starting materials such as 1,4-naphthoquinone and cyclopentadiene. The synthesis of an unprecedented octacyclic cage compound through intramolecular Diels-Alder (DA) reaction as a key step is described. The structures of three new cage compounds 7, 12 and 18 were confirmed by single crystal X-ray diffraction studies.
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai-400 076, India, .
authors.forename: Sambasivarao
authors.initials: S
authors.lastname: Kotha
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai-400 076, India, .
authors.forename: Mohammad
authors.initials: M
authors.lastname: Saifuddin
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai-400 076, India, .
authors.forename: Rashid
authors.initials: R
authors.lastname: Ali
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai-400 076, India, .
authors.forename: Gaddamedi
authors.initials: G
authors.lastname: Sreevani
keywords: Diels–Alder reaction; Grignard reaction; cage molecules; ring-closing metathesis; spirocycles