Abstract:
A process for the production of optically active (S)- or (R) -ß-amino acids represented by the general formula (II): (II) [wherein R is optionally substituted, alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, aryl, or heteroaryl; and * represents an asymmetric carbon atom] and optically active (R)- or (S)-ß-amino acid esters represented by the general formula (III): (III) [wherein R and * are each as defined above; and R
Abstract:
This invention provides a 2-substituted-3-(4-tetrahydropyranyl)-3-oxopropanoic ester represented by general formula (1) wherein Y represents a halogen atom or an acyloxy group, and R represents a hydrocarbon group, and a process for producing the same.
Abstract:
A flame-retardant resin composition which is excellent in flame retardancy and impact properties. The flame-retardant resin composition is characterized by comprising: (A) a polyamide resin; (B) a flame retardant comprising a component (B1) which is (b1) a phosphinic acid salt represented by the following formula (I), and/or (b2) a diphosphinic acid salt represented by the following formula (II), and/or a polymer formed from at least one of the (b1) and (b2) and a component (B2) which is (b3) a condensate of melamine, and/or (b4) a product of the reaction of melamine with phosphoric acid, and/or (b5) a product of the reaction of a melamine condensate with phosphoric acid, and/or a mixture comprising at least two of the (b3) to (b5); (C) a red phosphorus; (D) an impact-resistant material; and (E) an inorganic filler.
Abstract:
Disclosed is a polythiourethane having high refractive index and low dispersibility which is obtained through a reaction between a polythiol component containing one or more polythiocarbonate polythiol (preferably one having a -(CO-S-R-S)- structure (wherein R represents a divalent hydrocarbon group) and a number average molecular weight of 200-2,500) and a polyisocyanate component containing a polyisocyanate and/or a polyisothiocyanate. This polythiourethane is useful for plastic lenses, prisms, optical fibers, substrates for information recording, colored filters, infrared absorbing filters and the like.
Abstract:
A process for producing an alkyl 3-(4-tetrahydropyranyl)-3-oxopropionate compound represented by the formula (1): (1) (wherein R and R may be the same or different and each represents a group not participating in the reaction, provided that R and R may be bonded to each other to form a ring optionally containing a heteroatom therein; and R represents a hydrocarbon group), characterized by reacting a 4-acyltetrahydropyran represented by the formula (2): (2) (wherein R and R have the same meanings as defined above) with a carbonic diester represented by the formula (3): (3) (wherein R has the same meaning as defined above, provided that the two R 's may be bonded to each other to form a ring) in the presence of a base. Also provided is a process for producing the 4-acyltetrahydropyran.