G. V. Kryshtal

An unusual reaction of trichloromethane with acylals in the interphase catalysis conditions.

Abstract Aldehyde diacetates react with trichloromethane in the standard interphase catalysis conditions to form α-trichloromethylcarbinols or their acetates depending on temperature and time of the reaction.

Simple synthesis of 2-alkenyl- and 2-aryl-substituted 1,1-dichloroethylenes from unsaturated aldehydes

ConclusionsA three-step synthesis has been proposed for the preparation of 2-alkenyl- and 2-aryl-1,1-dichloroethylenes, involving the conversion of an aldehyde to its acylal (or α-trichloromethylcarbinol), α-trichloromethylcarbinol acetate, and 2-substituted 1,1-dichloro-olefin. The best procedure for the dechloroacetoxylation by the action of zinc powder in a mixture of acetic acid and ether.

A new pathway for the synthesis of 2,2-dimethyl-3,3-dichlorocyclopropanecarboxylic acid

ConclusionsA new pathway has been proposed for the synthesis of 2,2-dimethyl-3,3-dichlorocyclopropanecarboxylic acid from dimethylvinylcarbinol.

Synthesis of diethylamides of α-diethylaminocarboxylic acids using α-trichloromethylcarbinols and their acetates under phase-transfer catalysis conditions

ConclusionsTrichloromethyicarbinols and their acetates react with diethylamine under phase-transfer catalysis conditions to give diethylamides of α-diethylaminocarboxylic acids. The same products are formed in the reaction of aldehyde acylals with chloroform and diethylamine in the 50% aqueous NaOH-BTEAC phase-transfer catalytic system.

Synthesis of 2-(3-phenoxyphenyl)isovaleric acid and its esters having insecticidal activity

Conclusions2-(3-Phenoxyphenyl)isovaleric acid and several of its esters with insecticidal properties were synthesized.

Synthesis of pyrethroids with an α-trichloromethyl group in the alcoholic fragment

Conclusions1.A general method was developed for synthesizing substituted α-trichloromethylbenzyl alcohols from acylals of aromatic aldehydes.2.A series of pyrethroids of a new type with an α-trichloromethyl group in the alcoholic fragment of the molecule was synthesized.

Stereochemistry of Horner-Emmons reaction between 3-functionally substituted 2-methyl-2-propenylphosphonates and aliphatic aldehydes. 3. Effect of the acyclic and dioxaalkylene substituents at the phosphorus atom

The steric selectivity of the Horner-Emmons reaction between isovaleraldehyde and 3-carboethoxy-2-methyl-2-propenylphosphonates depends on the structure of the alkoxy substituants at the phosphorus atom. The use of five- and six-membered cyclic phosphonates permits us to prepare esters of3,7-dimethyl- 2,4-octadienoic acids with the predominance of the 2Z,4E isomer.

Stereochemistry of the Horner-Emmons reaction between 3-functionally substituted 2-methyl-2-propenylphosphonates and aliphatic aldehydes. 4. Effect of the nature of the aliphatic aldehyde and concentration of the starting reagents

The double bond formed in the Horner-Emmons reaction has only E configuration independently of the structure of the saturated linear, α-branched, and β-branched aliphatic aldehydes upon their reaction with the diethyl ester of 3-ethoxycarbonyl-2-methyl-2-propenylphosphonic acid, while the ratio of the2E,4E and2Z,4E isomers in the reaction product varies only from 58∶42 to 62∶38. An increase in the aldehyde concentration leads to an increase in the fraction of the2Z,4E isomer in the ethyl ester of 2E/Z,4E-3,7-dimethyl-2,4-octadienoic acid formed.

Stereochemistry of the Horner-Emmons reaction of 3-functionalized 2-methyl-2-propenylphosphonates with aliphatic aldehydes 5. Effects of base anion, temperature, solvent, and addition of a crown ether

Taking the reaction of diethyl 3-ethoxycarbonyl-2-methyl-2-propenylphosphonate with 3-methylbutanal as an example, it has been shown that the composition of the equilibrium mixture of the E- and Z-isomers of the starting phosphonate formed in the presence of bases is independent of the base anion (KOH or K2CO3) and the solvent (benzene or DMSO). In the mixture of 2E,4E- and 2Z,4E-isomers of ethyl 3, 7-dimethyl-2, 4-octadienoate formed in this reaction, the proportion of the 2E, 4E-ester falls as the temperature is reduced from +40 to −40‡C; the proportion of the 2E, 4E-ester in the heterophase system base/aprotic solvent increases with increasing polarity; and in the presence of 10 mole % of 18-crown-6 ether the proportion of the 2E, 4E-isomer is increased, being greater than 50% in all solvents. These findings indicate that the stereochemical outcome of the reaction depends on the balance between the phase systems and the chemical equilibria, including the formation, dissociation, and reactions of the intermediate products.

REACTION OF CITRAL WITH ACETONE CYANOHYDRIN AND DIETHYLAMINE, AND THERMOLYSIS OF THE RESULTING AMINONITRILE

The reactions of citral with acetone cyanohydrin and secondary amines (diethylamine, piperidine, morpholine, and N-methylaniline) to give 2-substituted amino-4, 8-dimethyl-3,7-nonadienoic acid nitriles have been examined. Possible path-ways for these reactions are discussed. The thermolysis of 2-diethylamino-4,8-dimethyl-3, 7-nonadienoic acid nitrile has been examined in solution, to give irreversibly 3-cyano-1-diethylamino-3,7-dimethyl-1,6-octadiene, this reaction proceeding faster in polar than in nonpolar solvents.