Direct conversion of benzene to phenol was achieved by allowing it to react with a mixed gas of air and CO in the presence of HPMoV and a very small amount of Pd-5%/C in aqueous acetic acid at 150 degrees C for 2h. The TON of HPMoV for the formation of phenol goes up to over 1300. The active species of the present reaction is thought to be V4+ generated from HPMoV catalyst by the reduction with CO. The role of the I'd species seems to promote the generation of V4+ from HPMoV. This method is expected to provide a direct route to phenol from benzene. (C) 2008 Elsevier B.V. All rights reserved.