triethanolamine vanadate cycloaliphatic vanadates such as cyclohexyl vanadate aryl vanadates such as phenyl vandate and silyl vanadates such as triphenylsilyl vanadate the amount of catalyst is such that the weight of vanadium in the combined state is between 0 0001 and 5 of the weight of the dehydrolinalol and preferably between 0 01 and 2 as with the known processes the process according to the invention can be carried out in the presence or absence of a solvent if a solvent is used it should be substantially inert so as not to react chemically with the catalyst or the reactants in particular they can be chlorinated or non chlorinated aliphatic cycloaliphatic or aromatic hydrocarbons nitrated aromatic hydrocarbons ethers or amides as the first co catalyst suitable for use in the practice of the process according to the invention there may be mentioned lauryl alcohol myristyl alcohol palmityl alcohol and stearyl alcohol also referred to as n dodecan 1 ol n tetradecan 1 ol n hexadecan 1 ol and n octadecan ol respectively and alkanepolyols preferably diols as the second co catalyst which may be used there may be mentioned n octan 1 ol n heptan 1 ol n decan 1 ol 2 ethyl cyclohexanol and 2 ethyl hexan 1 ol the reaction temperature is generally between 50 u00b0 and 300 u00b0 c and preferably.