Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact: purchase@heterocycles.com

Price: ¥ 4,320 (Yen only)
Period: This Article can be accessed for 7 days.

Paper | Regular issue | Vol 36, No. 8, 1993, pp.1803-1808
Published online, 1st January, 1970
DOI: 10.3987/COM-93-6364
Synthesis of 5-Aryl-3-hydroxy-4H-pyran-4-ones

Hisashi Takao,* Yoshinori Endo, and Tokunaru Horie

*Naruto Research Center, Otsuka Chemical Company, Ltd., S atoura,Naruto 772, Japan

Abstract

The palladium-catalyzed coupling reaction of 3-benzyloxy-5-bromo-2-methyl-4H-pyran-4-one (2b) with phenylboronic acid afforded efficiently 3-benzyloxy-2-methyl-5-phenyl-4H-pyran-4-one (3b-1), and the benzyloxy group of the resultant product was cleaved by hydrolysis with conc. hydrochloric acid in acetic acid to give 5-phenyl-3-hydroxy-2-methyl-4H-pyran-4-one (4b-1) in high yield. This method was applicable as a general method for synthesizing 5-aryl-3-hydroxy-4H-pyran-4-ones (4) from the 5-bromo-4H-pyran-4-ones (1).