To obtain a new methoxyalcohol derivative which is useful as a raw material for synthesizing retinal that is the basic raw material of carotenoids important in the fields of medicines, feed additives, plants, food additives, and so on.
A methoxyalcohol derivative of formula I. The compound of formula I is obtained, for example, by reacting (A) a diol derivative of formula II with methanol in the presence of (B) an acid catalyst [for example, tin (II) chloride, tin (IV) chloride, zinc chloride, iron (III) chloride, a rare earth metal triflate, hydrobromic acid or hydrochloric acid] preferably at -78°C to the boiling point of a solvent to be used to selectively methylate the secondary hydroxyl group. The component B is preferably used in an amount of about 0.01 to 1 mole time that of the component A. Retinal is obtained by oxidizing the compound of formula I with an oxidizing agent such as manganese dioxide to prepare the methoxyaldehyde derivative of formula III, and then removing the methoxy group of the compound of formula III.
KONYA NAOTO
TAKAHASHI TOSHIYA
Next Patent: PRODUCTION OF RETINAL AND INTERMEDIATE