- Cobalt-Catalyzed Reductive Dimethylcyclopropanation of 1,3-Dienes
-
Dimethylcyclopropanes are valuable synthetic targets that are challenging to access in high yield using Zn carbenoid reagents. Herein, we describe a cobalt-catalyzed variant of the Simmons–Smith reaction that enables the efficient dimethylcyclopropanation of 1,3-dienes using a Me2CCl2/Zn reagent mixture. The reactions proceed with high regioselectivity based on the substitution pattern of the 1,3-diene. The products are vinylcyclopropanes, which serve as substrates for transition-metal-catalyzed ring-opening reactions, including 1,3-rearrangement and [5+2] cycloaddition. Preliminary studies indicate that moderately activated monoalkenes are also amenable to dimethylcyclopropanation under the conditions of cobalt catalysis.
- Werth, Jacob,Uyeda, Christopher
-
p. 13902 - 13906
(2018/10/02)
-
- Method for producing cyclopropanecarboxylates
-
There is disclosed a method for producing cyclopropanecarboxylates of the formula (3): by transesterification in the presence of a lanthanoid metal alkoxide
- -
-
-
- Process for producing cyclopropanecarboxylates
-
There is disclosed a process process for producing a cyclopropanecarboxylate of formula (1): 1which process comprises reacting cyclopropanecarboxylic acid of formula (2): 2with a monohydroxy compound of formula (3): R6OH??(3),in the presence of a catalyst compound comprising an element of to Group 4 of the Periodic Table of Elements.
- -
-
-
- Asymmetric copper complex and cyclopropanation reaction using the same
-
There are disclosed asymmetric copper complex comprising, as components, (a) an optically active bisoxazoline compound of formula (1): wherein R1 and R2 are different and each represent a hydrogen atom, an alkyl group, a cycloalkyl group, or a phenyl or aralkyl group which may be substituted, R3 and R4 each represent a hydrogen atom, an alkyl group, a cycloalkyl group, or a phenyl or aralkyl group which may be substituted, or R3 and R4 may be bonded to each other to form a C3-5 cyclic alkylene group, R5 represents a hydrogen atom or a C1-6 alkyl group, or the two R5 groups may be bonded to each other to represent a C3-5 cyclic alkylene group, (b) a monovalent or divalent copper compound, and (c) a strong acid or a Lewis acid or a mixture thereof, and a process for producing an optically active cyclopropanecarboxylate using the same.
- -
-
-
- Monoclonal antibodies to synthetic pyrethroids and method for detecting the same
-
Methods are described for making specific monoclonal antibodies which may be used in a sensitive immunoassay for detection of synthetic pyrethroids in foods and environmental samples. Appropriate sample preparation and enzyme amplification of the immunoassay for this widely-used class of pesticides permits detection at low levels in laboratory and field tested samples.
- -
-
-
- Insecticidal resin coating film
-
An insecticidal resin coating film comprising a combination of an acrylonitrile and/or methacrylonitrile copolymer resin and an insecticidal component selected from the group consisting of specified compounds exhibits an insecticidal effect, since the compound is kept on the surface of the coating film in a state capable of exhibiting its insecticidal effect for a long period of time.
- -
-
-
- Process for preparing cyclopropane-carboxylic acid esters
-
A process for preparing an organic acid ester of the formula (I), EQU1 wherein R1 is a hydrogen atom or a methyl group, R2 is a methyl group, a vinyl group, a 2,2-dichlorovinyl group, a 1-propenyl group, a 2-methyl-1-propenyl group, a 2-carbomethoxy-1-propenyl group, a 2-methoxymethyl-1-propenyl group, a 1,3-butadienyl group, a 2-methyl-1,3-butadienyl group or a cyclopentylidenemethyl group when R1 is a hydrogen atom, and R2 is a methyl group when R1 is a methyl group; which comprises reacting an acid of the formula (II), EQU2 wherein R1 and R2 are each as defined above, or its reactive derivative, or mixture of the acid and its reactive derivative with a quaternary ammonium salt of the formula (III), SPC1 wherein X is a halogen atom, A is an alkylamine, pyridine or an N-alkylaniline.
- -
-
-
