The Chemistry of 1,2,3-Thiadiazoles, Volume 62

1.1 Cyclization of Hydrazones with Thionyl Chloride (Hurd–Mori Synthesis).

1.1.1 Scope and Limitations.

1.1.2 Mechanism of the Hurd–Mori Reaction.

1.1.3 Application of the Hurd–Mori Reaction in Organic Synthesis.

1.2 Cycloaddition of Diazoalkanes onto a C=S bond (Pechmann Synthesis).

1.3 Heterocyclization of α-diazo Thiocarbonyl Compounds (Wolff Synthesis).

1.3.1 Introduction of a Diazo Function into Compounds Containing a C=S Bond.

1.3.2 Introduction of a C=S Bond in the α-position to a Diazo Group.

1.3.3 Simultaneous Introduction of Diazo and Thiocarbonyl Functions.

1.4 Transformations of other Sulfur-containing Heterocyclic Compounds.

1.5 Elaboration of Preformed 1,2,3-Thiadiazoles.

1.5.1 Carboxylic Acids.

1.5.2 Functional Derivatives of Carboxylic Acids.

1.5.3 Aldehydes.

1.5.4 Amino-1,2,3-Thiadiazoles.

1.5.5 Halo Derivatives.

1.5.6 5-Hydrazino-, 5-Mercapto-1,2,3-Thiadiazoles and 5-Sulfide Derivatives.

1.5.7 2-(1,2,3-Thiadiazol-5-yl)acetic Acid Derivatives.

1.5.8 Alkenyl-1,2,3-Thiadiazoles.

1.5.9 5-Hydroxyiminomethyl- and 5-Diazomethyl-1,2,3-Thiadiazoles.

1.5.10 4-Hydroxymethyl-1,2,3-Thiadiazoles.

1.6 Tables.

1.7 Selected Procedures.

1.7.1 1,2,3-Thiadiazole-4-Carbaldehyde.

1.7.2 4-Phenyl-1,2,3-Thiadiazole.

1.7.3 4-Phenyl-1,2,3-Thiadiazole-5-Carbaldehyde.

1.7.4 4-Phenyl-5-Oxyiminomethyl-1,2,3-Thiadiazole.

1.7.5 5-Phenyl-1,2,3-Thiadiazole-4-Carbaldehyde.

1.7.6 5-Chloro-1,2,3-Thiadiazole-4-Carbaldehyde.

1.7.7 Ethyl 5-amino-1,2,3-Thiadiazole-4-Carboxylate.

1.7.7.1 Pechmann Method.

1.7.7.2 Wolff Method.

1.7.8 Ethyl 5-chloro-1,2,3-Thiadiazole-4-Carboxylate.

1.7.9 4-Phenyl-2-(2,4,6-Trichlorophenyl)-1,2,3-Thiadiazolium Chloride.

1.7.10 5-Amino-4-ethoxycarbonyl-2-phenyl-1,2,3-thiadiazolium bromide.

References.

2 Structure of 1,2,3-Thiadiazoles.

2.1 Theoretical Methods.

2.2 Experimental Structural Methods.

2.2.1 X-ray Analysis.

2.2.2 Nuclear Magnetic Resonance Spectroscopy.

2.2.2.1 Proton NMR Spectroscopy.

2.2.2.2 Carbon-13 NMR Spectroscopy.

2.2.2.3 Nitrogen-14 NMR Spectroscopy.

2.2.2.4 Nitrogen-15 NMR Spectroscopy.

2.2.3 Mass Spectrometry.

2.2.4 Other Spectroscopic Data.

References.

3 Chemical Properties of 1,2,3-Thiadiazoles.

3.1 Reactions due to the Reactivity of Ring Atoms.

3.1.1 Reactions with Electrophiles.

3.1.1.1 Protonation.

3.1.1.2 Complexation.

3.1.1.3 Alkylation.

3.1.1.4 Acylation.

3.1.1.5 Oxidation.

3.1.1.6 Electrophilic Substitution of Hydrogen.

3.1.2 Reactions with Nucleophiles.

3.1.2.1 Attack at the Sulfur Atom.

3.1.2.2 Attack at the C5 Atom.

3.1.2.3 Attacks at H4 and H5.

3.1.2.4 Cycloaddition Reactions.

3.2 Reactions of Substituents.

3.2.1 5-Alkyl-1,2,3-thiadiazoles.

3.2.2 1,2,3-Thiadiazole-4-carbaldehyde.

3.2.3 5-Amino-1,2,3-thiadiazole-4-carbothioamide.

3.2.4 Mercapto-1,2,3-thiadiazoles.

3.3 Rearrangements.

3.3.1 Dimroth-type Rearrangements.

3.3.2 Cornforth-type Rearrangements.

3.3.2.1 Rearrangements of 4-(iminomethyl)-substituted-1,2,3-Thiadiazoles.

3.3.2.2 Degenerate Rearrangements of 4-Thiocarbamoyl-1,2,3-Thiadiazoles.

3.3.2.3 Rearrangements of 1,2,3-Thiadiazoles Bearing Diazo, Azido and Hydrazono Groups in the 5-Position.

3.3.2.4 Tandem Rearrangements.

3.4 Ring Cleavage of 1,2,3-Thiadiazoles.

3.4.1 Thermal Decomposition.

3.4.2 Photochemical Decomposition.

3.4.3 Base-catalyzed Decomposition.

3.4.4 Oxidative and Reductive Processes.

3.4.5 Other Processes for Ring Cleavage.

References.

4 Fused 1,2,3-Thiadiazoles.

4.1 1,2,3-Thiadiazoles Fused with Five-Membered Rings.

4.1.1 Cyclopenteno-1,2,3-thiadiazoles.

4.1.2 Pyrrolo[2,3-d][1,2,3]thiadiazoles.

4.1.3 Pyrrolo[3,2-d][1,2,3]thiadiazoles.

4.1.4 Pyrrolo[3,4-d][1,2,3]thiadiazoles.

4.1.5 4,6-Dihydrofurano[3,4-d][1,2,3]thiadiazoles.

4.1.6 Thieno[2,3-d][1,2,3]thiadiazoles.

4.1.7 Thieno[3,2-d][1,2,3]thiadiazoles.

4.1.8 Thieno[3,4-d][1,2,3]thiadiazoles.

4.1.9 Selenopheno[3,4-d][1,2,3]thiadiazole.

4.1.10 Benzoselenopheno[3,2-d][1,2,3]thiadiazole.

4.2 1,2,3-Thiadiazoles Fused with Six-Membered Rings.

4.2.1 Cyclohexeno-1,2,3-thiadiazoles.

4.2.2 Benzo-1,2,3-thiadiazoles.

4.2.3 Piperidino[3,4-d][1,2,3]thiadiazoles.

4.2.4 1,2,3-Thiadiazolo[4,5-b]pyridines.

4.2.5 1,2,3-Thiadiazolo[4,5-c]pyridines.

4.2.6 1,2,3-Thiadiazolo[5,4-c]pyridines.

4.2.7 1,2,3-Thiadiazolo[5,4-d]pyrimidines.

4.2.8 1,2,3-Thiadiazolo[4,5-d]pyrimidines.

4.2.9 Pyrano[3,4-d][1,2,3]thiadiazole.

4.2.10 Thiopyrano[4,3-d][1,2,3]thiadiazoles.

4.2.11 Thiopyrano[2,1-d][1,2,3]thiadiazole.

4.2.12 Selenopyrano[4,3-d][1,2,3]thiadiazoles.

4.3 1,2,3-Thiadiazoles Fused with Seven-Membered Rings.

4.3.1 Benzooxepino- and Benzothiepino[3,4-d][1,2,3]thiadiazoles.

4.3.2 Thiadiazolo[5,4-d]benzazepines.

4.3.3 1,2,3-Thiadiazolo[5,4-b][1,5]benzodiazepine.

4.4 Bicyclic 1,2,3-Thiadiazoles of Azathiapentalenic Structure.

References.

5 Synthesis and Properties of 1,2,3-Selenadiazoles.

5.1 Synthesis of 1,2,3-Selenadiazoles.

5.1.1 Oxidative Cyclization of Hydrazones by Se-containing Reagents.

5.1.2 Cycloaddition Reactions of Diazoalkanes with Compounds Containing C=Se Bonds.

5.1.3 Elaboration of Preformed 1,2,3-Selenadiazoles.

5.1.4 Miscellaneous Syntheses.

5.2 Structural Data of 1,2,3-Selenadiazoles.

5.2.1 Mass Spectrometry.

5.2.2 Proton NMR Spectroscopy.

5.2.3 Carbon-13 NMR Spectroscopy.

5.2.4 Nitrogen-15 NMR Spectroscopy.

5.2.5 Selenium-77 NMR Spectroscopy.

5.2.6 X-ray Crystallography.

5.2.7 Miscellaneous.

5.3 Reactivity of 1,2,3-Selenadiazoles.

5.3.1 Ring Cleavage.

5.3.1.1 Thermal Reactions.

5.3.1.2 Photochemical Reactions.

5.3.1.3 Base-catalyzed Reactions.

5.3.1.4 Radical-catalyzed Reactions.

5.3.1.5 Reaction with Metal Complexes.

5.3.1.6 Miscellaneous Ring Cleavage Reactions.

5.3.2 Formation of Salts and Ylides.

5.4 Fused 1,2,3-Selenadiazoles.

5.4.1 Bicyclic 1,2,3-Selenadiazoles.

5.4.2 Tricyclic 1,2,3-Selenadiazoles.

5.4.3 Tetra- and Pentacyclic 1,2,3-Selenadiazoles.

5.5 Applications of 1,2,3-Selenadiazoles.

References.

6 1,2,3-Thiadiazoles in Medicine and Agriculture.

6.1 Medicine.

6.2 Agriculture.

6.2.1 Thidiazuron.

6.2.2 Bion.

References.

Index.