摘要:
The invention provide a process for producing vitamin A aldehyde in high yield by oxidizing vitamin A with a aldehyde of the general formula (1) ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are the same or different and respectively represents a lower alkyl group or a lower alkenyl group in the presence of aluminum alkoxide in a catalytic amount.
摘要:
The present invention provides a novel process for producing .alpha.,.beta.-unsaturated aldehydes including industrial important fragrances such as citral and sinensal, starting materials for preparing pharmaceutical drugs such as senecioaldehyde, farnesal, 8-acetoxy-2,6-dimethyl-2,6-octadienal and the like, directly and in high yield, from formic acid esters of allylic alcohols in the presence of a catalytic amount of aluminum alkoxide by the oxidation of the corresponding alehyde.
摘要:
The present invention provides a process for preparing halogenated sulfones by reacting a halogenating agent with a salt of a hydroxysulfone. The halogenated sulfones are useful as an intermediate for vitamin A or its carboxylic acid esters employed as medicines or feed additives.
摘要:
Provided is a novel process for readily producing .beta.-carotene by reacting a sulfone compound represented by the general formula (1), (2) or (3) with an alkali, ##STR1## wherein R represents a phenyl group which may be substituted, R' a protecting group of acetal type and X a halogen atom.
摘要:
Provided is a novel process for readily producing .beta.-carotene in which a sulfone compound represented by the general formula (1), (2) or (3) is reacted with an alkali, ##STR1## wherein R represents a phenyl group which may be substituted, R' a protecting group of acetal type and X a halogen atom.
摘要:
The invention provides a novel process for produing .alpha. -keto-carboxylic acid esters that are useful as intermediates for the preparation of pharmaceutical drugs in high yield by oxidizing .alpha. -hydroxycarbocylic acid esters with hypochlorous acid in the presence of nitroxy radical.
摘要:
A process for producing vitamin A acid, having useful biological activity, which comprises oxidizing vitamin A aldehyde with an aqueous solution of an alkali metal chlorite in the presence of an acid.
摘要:
The invention provides a process for producing vitamin A or its carboxylic acid ester by treating inexpensive and readily available industrial starting materials with potassium hydroxide which is widely employed industrially and is inexpensive.
摘要:
A process for preparing an allylic sulfone of the following general formula (I), ##STR1## wherein, R is a hydrogen atom or a lower alkyl group, and containing both cis and trans isomers, by a reaction of a compound selected from the group consisting of geranyl chloride, neryl chloride, and linalyl chloride with a phenyl sulfinate of the following general formula (III), ##STR2## wherein, R is a hydrogen atom, or a lower alkyl group, and M is a sodium atom or potassium atom, in the presence of (i) tetralkylammonium iodide in an anhydrous condition or (ii) a zinc halide and an iodide.
摘要:
Chlorinated olefins of general formula (I), ##STR1## wherein R is an alkyl, aralkyl, or alkenyl group substituted or not substituted by a lower acyloxy, lower alkyloxy, alkenyloxy or benzyloxy group, are prepared by the reaction of hypochlorous acid, generated by the reaction of sodium hypochlorite with a strong mineral acid, and olefins of general formula (II), ##STR2## wherein R is the same as defined above, in a two-phase system of water phase and organic solvent phase, not being miscible with water.