Patent US4146582 (http://l2.espacenet.com/dips/viewer?PN=US4146582&CY=gb&LG=en&DB=EPD)
. The reference was given by Vitsh. It`s not actually using MnO2 and is somewhat more "complicated" but still good one.Post 208702 (https://www.thevespiary.org/talk/index.php?topic=7285.msg20870200#msg20870200)
(Antoncho: "The easiest synth of benzaldehyde from toluene", Chemistry Discourse)Post 224776 (https://www.thevespiary.org/talk/index.php?topic=7382.msg22477600#msg22477600)
(fructose: "P2P - 100% OTC !?!", Chemistry Discourse)Post 208702 (https://www.thevespiary.org/talk/index.php?topic=7285.msg20870200#msg20870200)
(Antoncho: "The easiest synth of benzaldehyde from toluene", Chemistry Discourse)Post 208782 (https://www.thevespiary.org/talk/index.php?topic=7285.msg20878200#msg20878200)
(PolytheneSam: "Re: The easiest synth of benzaldehyde from toluene", Chemistry Discourse)http://www.geocities.com/dritte123/PSPF.html (http://www.geocities.com/dritte123/PSPF.html)