A series of Losartan analogues 1-12 with different functional groups were synthesized and characterized. In comparison with the previous reports, the synthetic procedures described in this paper have been optimized as follows below: 1) preparation of aromatic amine 15 and 18 through hydrogenation by employing Raney Ni and hydrazine as catalysts in place of palladium; 2) preparation of nitro-compound
Base catalysed rearrangements involving ylide intermediates. Part 13. Further rearrangements of 2-oxidoanilinium ylides
作者:W. David Ollis、Ratnasamy Somanathan、Ian O. Sutherland
DOI:10.1039/p19810002930
日期:——
The 2-oxidoanilinium ylides (7) rearrange on heating to give the ethers (10) together with the dienones (8) and the phenols (11) for cases where the aromatic ring has a 5-alkyl substituent or a mixture of the dienones (8) and (12) for cases where the aromatic ring is 3,5-disubstituted. A study of the deuteriated ylides (25) shows that these reactions involve competing concerted and radical-pair processes
Metal-free direct annulation of 2-aminophenols and 2-aminothiophenols with unactivated amides through transamidation: Access to polysubstituted benzoxazole and benzothiazole derivatives
hydrochloride played a crucial role in amide activation followed nucleophilic attack that through eliminations of amine as a side product, and de-hydrolysis step leads to final annulation. This versatile strategy is applicable to a wide variety of differently substituted o-aminophenols, unactivated aliphatic and aromatic amides, yielding the corresponding product in good to excellent yields in a single step