Tandem annulation strategy for the convergent synthesis of benzonaphthopyranones: total synthesis of chartarin and O-methylhayumicinone
作者:Sutapa Ray、Asit Patra、Dipakranjan Mal
DOI:10.1016/j.tet.2008.01.039
日期:2008.3
A Hauser-initiated tandem annulation has been developed for the rapid regiospecific synthesis of benzonaphthopyranones via formation of two rings in one-pot operation. This strategy has been generalized with benzonaphthopyranones 26, 29, 32, and 35. It has also been employed in a short synthesis of chartarin (3) and O-methylhayumicinone (67).
A novel three-step synthetic route to 1,4-anthraquinones
作者:Gita Majumdar、Kadiyala V.S.N. Murty、Dipakranjan Mal
DOI:10.1016/0040-4039(94)88098-0
日期:1994.8
The anionic [4+2] cycloaddition (1→3) and the retro [4+2] cycloaddition (3→ 4) are coupled to evolve a general and high yielding three-step synthesis of 1,4-anthraquinones.
Regiospecific Synthesis of Benzo[<i>b</i>]fluorenones via Ring Contraction by Benzil-Benzilic Acid Rearrangement of Benz[<i>a</i>]anthracene-5,6-diones
作者:Dipakranjan Mal、Asit Patra、Sujit Ghorai、Saroj De
DOI:10.1055/s-2006-942468
日期:2006.8
A regiospecific route to benzo[b]fluorenones is described. The synthesis is based upon a one-pot, regiospecific benzannulation of 1,4-dipolar synthons with naphthoquinone monoketal and ring contraction of the generated benz[a]anthracene-5,6-diones through benzil-benzilic acid rearrangement.