Annulated oxa-cage frameworks via Claisen rearrangement and ring-closing metathesis. Issue 49 (4th December 2020)

• Record Type: Journal Article
• Authors: Kotha, Sambasivarao; Cheekatla, Subba Rao; Chaurasia, Usha Nandan
• Is Part Of: Tetrahedron. Volume 76:Issue 49(2020)
• Publication Date: 2020-12-04
• Subjects: Oxa-cages -- Heterocycles -- Cycloadditions -- Transannular cyclization -- Claisen rearrangement -- Ring-closing metathesis; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2020.131694
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: In our quest to design high-density fuels, we report a variety of structurally interesting new annulated oxa-cage frameworks. Here, we investigated a linear synthetic sequence, which relies on reductive C–C bond cleavage and ring-closing metathesis as key steps. For this purpose, we utilized inexpensive and readily available starting materials such as hydroquinone and endo -dicyclopentadiene. Transannular cyclization during Grignard addition played a significant role in the design of intricate caged compounds. The creation of these new oxa-cage systems is a challenging task by traditional methods. The structure of the target compound has been unambiguously established by single-crystal X-ray diffraction studies. These data indicate that density of the RCM compound is larger than the cubane density. Graphical abstract: Image 1 Highlights: Oxa-cage compounds were synthesized via cycloadditions and ring closing metathesis (RCM). Transannular cyclization was observed in the Grignard addition. Novel dioxa cage compound was prepared by RCM. The target oxa-cage has been proven by single crystal X-ray diffraction studies.