Regioselective alkylation of juglones

ORGN 95

Thomas L. Mindt, Thomas.Mindt@pharma.ethz.ch, Department of Chemistry, Brown University, Providence, RI 02912 and Kathlyn A Parker, Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794.
The synthesis of quinols by 1,2-addition of organometallic reagents to asymmetrical quinones in a chemo-and regioselective fashion represents a formidable synthetic challenge. We wish to report the development of a methodology for the selective and efficient alkylation of 5-hydroxyl naphthoquinones (juglones) exploiting the effect of intramolecular hydrogen bonding. Organometallic reagents of moderate basicity add selectively to the more reactive carbonyl yielding C1-quinols as the sole product in good yields. Masking of the C1-carbonyl permits the alkylation of the remaining carbonyl providing access to protected C4-quinols. In addition, the scope and limitation of oxime protective groups in the context of quinone and quinol chemistry will be discussed.

 

New Reactions and Methodology, Materials, Total Synthesis, Process R&D
8:00 PM-10:00 PM, Sunday, 28 August 2005 Washington DC Convention Center -- Hall A, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 29 August 2005 Washington DC Convention Center -- Hall A, Sci-Mix

Division of Organic Chemistry

The 230th ACS National Meeting, in Washington, DC, Aug 28-Sept 1, 2005