摘要:
A process for producing an epoxide represented by general formula (1a) or (1b), which comprises reacting an olefin represented by general formula (2) with a compound containing iodine and an acyloxy ion and treating the reaction product under a basic condition so as to form an oxirane ring on the stereochemically crowded side of the feed olefin. In formulae (1a), (1b) and (2), R?1, R2, R3 and R4¿ represent each hydrogen, alkyl, alkenyl, aryl, alkoxy, aryloxy, acyl, alkoxycarbonyl, aryloxycarbonyl, aralkyl, silyl or silyloxy, provided that when each of these groups represents a divalent group, they may be combined together to represent a cyclic group, and that these groups may be the same or different from one another and further may be substituted or branched. The plane formed by the double bond, R?1, R2, R3 and R4¿ has one side which is stereochemically more crowded than the other side.
摘要:
Hydrated zirconium oxide modified with an organo-silicon compound, wherein 50-90 % of the hydroxyl groups present on the surface of hydrated zirconium oxide are substituted by said compound. The modified oxide can be efficiently utilized in the oxidation of an alcohol into an aldehyde or ketone and in the production of a lactone.
摘要:
A process for producing a nucleoside derivative (1) by reacting a substituted 2,3-dihydrofuran derivative (2) with an organohalogen compound (3) containing a group 16 element of the periodic table to give a substituted 2-halotetrahydrofuran derivative (4), condensing the derivative (4) with a nucleic acid base to give a substituted nucleoside derivative (5), and reducing the derivative (5), wherein R represents hydrogen, alkyl or R -O-CH2-; R to R represent each hydrogen or a group containing a group 14-17 element of the periodic table; R represents optionally substituted alkyl or phenyl; A represents a group 16 element of the periodic table; B represents a nucleic acid base; and X represents halogen.