Synthetic Pyrethroid Insecticides: Chemistry and Patents

A Synthesis of Important Pyrethroids.- 1 Synthesis of Pyrethroid Acids.- 1.1 Synthesis of Chrysanthemic Acid.- 1.1.1 Key-Reaction: Addition of Carbenes to Olefinic Bonds.- 1.1.2 Key-Reaction: Carbanion-Addition to Activated Olefinic Bonds Followed by 1,3-Cycloelimination for Introduction of Carbon No. 2 or 3.- 1.1.3 Key-Reaction: Claisen-Rearrangement for Precursors for 1,3-Cycloelimination.- 1.1.4 Key-Reaction: Cyclopropanes by Contraction of Larger Rings.- 1.1.5 Key-Reaction: di-?-Methane Rearrangement and Other Rearrangements.- 1.1.6 Optically Active Chrysanthemic Acid.- 1.1.6.1 Resolutions of Racemates and Isomerizations of Chrysanthemic Acid.- 1.1.6.2 Synthesis of Optically Active Chrysanthemic Acid.- 1.2 Synthesis of Nor-Chlorochrysanthemic Acid.- 1.3 Synthesis of Permethric Acid.- 1.3.1 Introduction of Carbon No. 1.- 1.3.1.1 Introduction of Carbon No. 1 by Addition of Carbenes Across Nonactivated Double Bonds.- 1.3.1.1.1 Synthesis of 1,1-Dichloro-4-methylpentadiene.- 1.3.1.2 Introduction of Carbon No. 1 by Addition of Carbanions to Activated Double Bonds.- 1.3.1.3 Introduction of Carbon No. 1 by Addition of Carbon Radicals to the Double Bond.- 1.3.2 Synthesis of Permethric Acid via Cyclizing 1,3-Dehydrohalogenation.- 1.3.2.1 Synthesis of 2,2-Dimethylpentenoic Acid Derivates as Key Intermediates for 1,3-Cycloeliminations.- 1.3.2.2 Synthesis of ?-Polychloro Substituted 2,2-Dimethyl-hexenoic Acid Derivatives and 2,2-Dimethyl-butyrolactones.- 1.3.3 Synthesis of Cyclopropane Carboxylic Acids by Contraction of Larger Rings.- 1.3.4 Permethric Acid from Caronaldehyde.- 1.3.5 Permethric Acid from Caronic Acid.- 1.3.6 Isomers and Isomerization of Permethric Acid.- 1.3.6.1 Separation of Racemic Mixtures of Stereoisomers.- 1.3.6.2 Synthesis of Racemic Stereoisomers.- 1.3.6.3 Resolution of Racemic Stereoisomers of Permethric Acid.- 1.3.6.4 Synthesis of Optically Active Permethric Acid.- 1.3.6.5 Stereoisomerization of Permethric Acid.- 1.3.6.6 Synthesis of Individual Enantiomers of Chrysanthemic Acid, Permethric Acid and Other Pyrethroid Acids from Optically Active Naturally Occurring ?-Pinene and Carene.- 1.4 Synthesis of Deltamethric Acid.- 1.5 Synthesis of Cyhalothric Acid.- 1.6 Synthesis of Flumethric Acid.- 1.7 Synthesis of Other Important Cyclopropane Pyrethroid Acids for Research, Development and Commerce.- 1.7.1 Olefination Reactions with Carone Aldehyde.- 1.7.2 Construction of the Cyclopropane Moiety from Activated Olefins and Nucleophiles.- 1.7.3 Precursors for Cyclopropanecarboxylic Acids by Claisen-Rearrangement for 1,3-CycloeHmination.- 1.7.4 Carbene Addition to Olefinic Bonds.- 1.7.5 Ring Contraction to Cyclopropane Carboxylic Acid.- 1.7.6 Cyclopropane Pyrethroid Acids as Precursors for Other Pyrethroid Acids.- 1.7.7 1-Aryl-cyclopropane Carboxylic Acids.- 1.8 ?-Phenylvaleric Acid and Cognate Acids.- 2 Synthesis of Important Pyrethroid Alcohols.- 2.1 Synthesis of 3-Phenoxybenzaldehyde and Derivatives.- 2.1.1 Synthesis of 3-Phenoxytoluene.- 2.1.2 Side-Chain Halogenation of 3-Phenoxytoluene.- 2.1.3 Oxidative Functionalization of 3-Phenoxytoluene.- 2.1.4 Synthesis of 3-Phenoxy-4-Fluorobenzaldehyde.- 2.1.5 Synthesis of 3-Phenoxy Benzaldehyde Cyanhydrine.- 2.2 Synthesis of 3-Phenyl Benzyl Alcohols.- 2.3 Heterocyclic Pyrethroid Alcohols.- 2.3.1 Synthesis of 3-Hydroxymethyl-5-Benzylfurane.- 2.3.2 Other Substituted Furylmethyl- and Allylalcohols.- 2.4 Cyclopentenolons.- 2.5 Polyfluorinated Benzylalcohols.- 3 Formation of the Pyrethroid-Ester-Linkage.- 3.1 General Esterification.- 3.2 Generation of ?-Cyano-3-Phenoxybenzyl Esters.- 3.2.1 Racemates.- 3.2.2 Single Optically Active Cyanohydrine Ester-Isomeres.- 3.3 Formation of Pyrethroid-Ester Components in the Final Step of Insecticide Synthesis.- 4 Non-Ester Pyrethroids.- B Patent Applications for Synthetic Pyrethroid ActiveIngredients.- 5 Analysis of International Pyrethroid Patent Activity.- 5.1 Compilation of Basic Patents for New Pyrethroid Active Ingredients.- Abbreviations.- Literature.