Work

Origin of Stereocontrol in the Construction of the 12-Oxatricyclo[6.3.1.02,7]dodecane Ring System by Prins−Pinacol Reactions

Year: 2009

Type: article

Abstract: Polycyclic products containing the 12-oxatricyclo[6.3.1.0(2,7)]dodecane moiety having either the trans (8a-e) or cis (9a-e) relative configuration of the oxacyclic bridge and the cis angular substituents are formed stereospecifically by Prins-pinacol cyclizations of unsaturated alpha-dithianyl acetals 14a-e or 15a-e. These results show that the topography (boat or chair) of the Prins cyclization of the sulfur-stabilized oxocarbenium ions generated from acetals 14a-e or 15a-e is controlled by the stereoelectronic influence of the allylic substituents, with steric effects playing a minor role. A complex molecular rearrangement that is terminated by a thio-Prins-pinacol reaction is also identified.

Source: The Journal of Organic Chemistry

DOI: 10.1021/jo9024144

Authors: Larry E. Overman, Paul S. Tanis

Institution: University of California, Irvine

Language: English

Topic: Organic Chemistry Synthesis Methods

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: GlaxoSmithKline, National Institute of Neurological Disorders and Stroke

Awards: G123414227, New Methods for the Synthesis of Neurological Agents