title: Synthesis and Applications of Hajos-Parrish Ketone Isomers.
abstract: Numerous natural products possess ring systems and functionality for which Hajos-Parrish ketone isomers with a transposed methyl group (termed "iso-Hajos-Parrish ketones") would be of value. However, such building blocks have not been exploited to the same degree as the more typical Hajos-Parrish hydrindane. An efficient three-step synthesis of such materials was fueled by a simple method for the rapid preparation of highly functionalized cyclopentenones, several of which are new chemical entities that would be challenging to access through other approaches. Furthermore, one iso-Hajos-Parrish ketone was converted into two distinct natural product analogues and one natural product. As one indication of the value of these new building blocks, that latter target was obtained in 10 steps, having previously been accessed in 18 steps using the Hajos-Parrish ketone.
authors.affiliation: Dept. of Chemistry, Columbia University, 3000 Broadway, New York, NY 10027 (USA).
authors.forename: James M
authors.initials: JM
authors.lastname: Eagan
authors.affiliation: Dept. of Chemistry, Columbia University, 3000 Broadway, New York, NY 10027 (USA).
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hori
authors.affiliation: Dept. of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458 (USA) http://www.scripps.edu/snyder/index.htm.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Wu
authors.affiliation: Dept. of Chemistry, Columbia University, 3000 Broadway, New York, NY 10027 (USA).
authors.forename: Kyalo Stephen
authors.initials: KS
authors.lastname: Kanyiva
authors.affiliation: Dept. of Chemistry, Columbia University, 3000 Broadway, New York, NY 10027 (USA). ssnyder@scripps.edu.|Dept. of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458 (USA) http://www.scripps.edu/snyder/index.htm. ssnyder@scripps.edu.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Snyder
mesh_terms: D001688:Biological Products / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D061565:Cycloaddition Reaction; D003517:Cyclopentanes / Q000138:chemical synthesis / Q000737:chemistry*; D007536:Isomerism; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D008745:Methylation
chemical_list: D001688:Biological Products; D003517:Cyclopentanes; D007659:Ketones; C013905:cyclopentenone
keywords: Diels-Alder reactions; Hajos-Parrish ketones; cascade reactions; cyclopentenones; total synthesis