Hydrogenation of some allylic alcohols catalysed by anchored montmorillonitebipyridinepalladium(II) acetate - A kinetic study

Abstract

462-467Hydrogenation of some allylic alcohols like 2-methyl-2-propen- l-ol, 4-penten-3-ol, trans-2-buten-l -ol, trans-3-penten-2-ol and 4- methyl-3-penten-2-ol has been carried out by anchored  montmorillonitebipyridinepalladium(II) acetate in THF medium. Under the reaction conditions 100% saturation of carbon-carbon double bond is observed and there is neither polymerisation nor isomerisation. The observed rate has been found to be first order each with respect to partial pressure of hydrogen and [substrate] and fractional order with respect to [catalyst] . The rate of hydrogenation follows the order: 2-methyl-2-propen-l-ol > 4-penten-3-ol <span style="font-size:14.0pt; font-family:Arial;mso-fareast-font-family:" times="" new="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">> <span style="font-size:14.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">trans-2-buten-l-ol <span style="font-size:14.0pt; font-family:Arial;mso-fareast-font-family:" times="" new="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">> <span style="font-size:14.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">trans -3-penten-2-ol <span style="font-size:14.0pt; font-family:Arial;mso-fareast-font-family:" times="" new="" roman";mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">> 4-methyl-3-penten-2-ol. Thermodynamic parameters have been evaluated, rate law and a plausible mechanism have been proposed.</span