作者:Virginia Mazzanti、Eduardo Antonio Della Pia、Martyn Jevric、Tue Heesgaard Jepsen、Anders Kadziola、Ole Hammerich、Mogens Brøndsted Nielsen
DOI:10.1080/17415993.2013.789515
日期:2013.12.1
Dibenzo[bc,fg][1,4]dithiapentalene (1) has previously been prepared by an intramolecular nucleophilic aromatic substitution (SNAr) reaction of 9-fluorodibenzo[b,d]thiophen-1-thiol (X, Y = S). Instead, subjecting 9-fluorodibenzo[b,d]benzofuran-1-ol (X, Y = O) to similar reaction conditions provided a macrocycle (5), as a result of an intermolecular SNAr cyclization, rather than dibenzo[bc,fg][1,4]dioxapentalene (3). To shed further light on this reaction type, we here present an attempt to prepare the mixed (O,S) compound dibenzo[bc,fg][1,4]oxathiapentalene (7) from 9-fluorodibenzo[b,d]thiophen-1-ol (11, X = S, Y = O). However, like a previous strategy to make this molecule, the attempt failed. We rationalize the results by a computational study of the reaction energetics and profiles of the SNAr reactions.[GRAPHICS].