A process for preparing an aldol ester of the formula (I), wherein at least one carboxylic anhydride of the formula (II) is reacted with at least one aldol of the formula (III) with heating in the presence of a basic catalyst with a pKa of the conjugate acid of at least 8, and the reaction product obtained from the process. The process provides a light-coloured and low-odour reaction product which has a high content of aldol ester content of the formula (I) and can be used, without elaborate purification steps, particularly without overhead distillation of the aldol ester, as a blocking agent for primary amines. The resultant blocked amines have a long storage life together with polymers containing isocyanate groups, and cure rapidly and reliably on contact with moisture to form mechanically high-grade and robust elastomers.

A process for preparing an aldol ester of the formula (I), wherein at least one carboxylic anhydride of the formula (II) is reacted with at least one aldol of the formula (III) with heating in the presence of a basic catalyst with a pKa of the conjugate acid of at least 8, and the reaction product obtained from the process. The process provides a light-coloured and low-odour reaction product which has a high content of aldol ester content of the formula (I) and can be used, without elaborate purification steps, particularly without overhead distillation of the aldol ester, as a blocking agent for primary amines. The resultant blocked amines have a long storage life together with polymers containing isocyanate groups, and cure rapidly and reliably on contact with moisture to form mechanically high-grade and robust elastomers.

The present invention disclosed 3-substituted phenylamidine compounds of general formula (I), wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.4a, R.sup.4b, A and E have the same meanings as defined in description. The present invention further discloses methods for their preparation and use of the compounds of general formula (I) as a crop protection agent.

##STR00001##

The present invention disclosed 3-substituted phenylamidine compounds of general formula (I), wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.4a, R.sup.4b, A and E have the same meanings as defined in description. The present invention further discloses methods for their preparation and use of the compounds of general formula (I) as a crop protection agent.

##STR00001##

Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

Disclosed is an imine-type quaternary ammonium salt catalyst, wherein the catalyst has a general structure formula shown by formula I below; in the formula, R1 and R2, respectively, are independently selected from a C1-C20 linear alkyl or a branched C3-C20 alkyl, and a C1-C20 hydroxylalkyl, a C3-C8 cycloalkyl, and arylated alkyl; R3 is a linear or branched alkyl, cycloalkyl or aryl; and R4 is hydrogen, aryl, a linear C1-C15 alkyl or branched C3-C15 alkyl. Also disclosed are a method for preparing the catalyst and a polyisocyanate composition prepared therefrom. The catalyst, by introducing an imine structure, on the basis of ensuring high catalytic activity thereof, is allowed to have properties of high temperature decomposition and inactivation, and when applied to the synthesis of polyisocyanate, can effectively prevent the risk of explosive polymerization caused by an uncontrolled reaction.

The present invention includes certain conchinine-derived phase-transfer catalysts of formula (I), compositions comprising the same, and methods of promoting asymmetric addition reactions using the same. ##STR00001##

The present invention includes certain conchinine-derived phase-transfer catalysts of formula (I), compositions comprising the same, and methods of promoting asymmetric addition reactions using the same. ##STR00001##