Benzyne arylation of oxathiane glycosyl donors

• Martin A. Fascione and
• W. Bruce Turnbull

Beilstein J. Org. Chem. 2010, 6, No. 19, doi:10.3762/bjoc.6.19

• Martin A. Fascione W. Bruce Turnbull School of Chemistry, University of Leeds, Leeds, LS2 9JT, UK 10.3762/bjoc.6.19 Abstract The arylation of bicyclic oxathiane glycosyl donors has been achieved using benzyne generated in situ from 1-aminobenzotriazole (1-ABT) and lead tetraacetate. Following

• sulfur arylation, glycosylation of acetate ions proceeded with high levels of stereoselectivity to afford α-glycosyl acetates in a ‘one-pot’ reaction, even in the presence of alternative acceptor alcohols. Keywords: benzyne; 1,2-cis-glycosides; glycosyl acetates; oxathiane glycosyl donors

• endeavours to achieve this goal and the first use of benzyne as an activating agent for thioglycosides [24]. Results and Discussion The method chosen for in situ benzyne (9) generation was the reaction of 1-aminobenzotriazole (1-ABT) (8) with lead tetraacetate by the procedure pioneered by Rees and co

Diels- Alder reactions using 4,7-dioxygenated indanones as dienophiles for regioselective construction of oxygenated 2,3-dihydrobenz[f]indenone skeleton

• Natsuno Etomi,
• Takuya Kumamoto,
• Waka Nakanishi and
• Tsutomu Ishikawa

Beilstein J. Org. Chem. 2008, 4, No. 15, doi:10.3762/bjoc.4.15

• and [4.4.3]propellane. The addition of Lewis acid did not affect the product ratio, whereas the use of the 6-bromoindanetrione exclusively afforded the latter propellane. On the other hand, DAR of benzyne derived from bromoindan and furan gave 5,8-epoxy-2,3-dihydrobenz[f]indene, which was subjected to

• B; quinone route) [28]; 2) regioselective ring-opening of 5,8-epoxy-2,3-dihydrobenz[f]indenone 11 derived from benzyne 10 and furan (9) (path C, benzyne route). Now we report that both of the methods are effective for the construction of the 2,3-dihydrobenz[f]indenone skeleton, but not for the

• ZnCl2, from which the phenol 20 and propellane 23 were isolated in low yields as conversion products (entry 11). The desired 4,8,9-trioxygenated 2,3-dihydrobenz[f]indenone-type compound 24 was not obtained in any of the experiments. Next, synthesis of 2,3-dihydrobenz[f]indenone via a benzyne route was