An expedient and new synthesis of pyrrolo[1,2-b]pyridazine derivatives

• Rajeshwar Reddy Sagyam,
• Ravinder Buchikonda,
• Jaya Prakash Pitta,
• Himabindu Vurimidi,
• Pratap Reddy Padi and
• Mahesh Reddy Ghanta

Beilstein J. Org. Chem. 2009, 5, No. 66, doi:10.3762/bjoc.5.66

• -methyl-3-oxo-pentanoic acid phenylamide with tertiary butyl carbazate and subsequent condensation of the resulting carbamate derivative with a chalcone provided a facile new approach to pyrrolo[1,2-b]pyridazine derivatives. Keywords: 1,4-diketone; migration and cyclization; pyrrolo[1,2-b]pyridazine

• ][10][11][12][13]. The synthesis and properties of pyrrolo[1,2-b]pyridazine derivatives were reviewed in 1977 by Kuhla and Lombardino [14]. Subsequently, new methods for the synthesis of these compounds have been described, which can be classified into two main approaches. The first involves

• ]. Pyrrolo[1,2-b]pyridazine derivatives can also be synthesized from 1-aminopyrrole and its derivatives. This original method was reported by Flitsch and Krämer (in 1968–9) [23][24], who obtained a series of unsubstituted pyrrolopyridazines from 1-aminopyrrole and β-dicarbonyl compounds. Benzoylacetone, on