13566-26-2

Basic information

• Product Name: dimethyl 3,3-dimethyl-3H-pyrazole-4,5-dicarboxylate
• CAS NO: 13566-26-2
• Molecular Formula: C₉H₁₂N₂O₄
• Molecular Weight: 212.2026
• Mol File: 13566-26-2.mol
• Article Data: 5

Chemical Properties

• Boiling Point: 270.7°C at 760 mmHg
• Flash Point: 112.7°C
• Density: 1.26g/cm³
• Vapor Pressure: 0.00675mmHg at 25°C
• Refractive Index: 1.53
• CAS DataBase Reference: dimethyl 3,3-dimethyl-3H-pyrazole-4,5-dicarboxylate(CAS DataBase Reference)
• NIST Chemistry Reference: dimethyl 3,3-dimethyl-3H-pyrazole-4,5-dicarboxylate(13566-26-2)
• EPA Substance Registry System: dimethyl 3,3-dimethyl-3H-pyrazole-4,5-dicarboxylate(13566-26-2)

Safety Data

• Hazardous Substances Data: 13566-26-2(Hazardous Substances Data)

Upstream product

• 1829-60-3 dimethyl 7-oxabicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate 
• 2684-60-8 2-diazopropane 
• 762-42-5 dimethyl acetylenedicarboxylate 
• 351197-69-8 5,5-dimethyl-2-(p-methylphenoxy)-2-phenoxy-Δ³-1,3,4-oxadiazoline 
• 452336-06-0 5,5-dimethyl-2-(o-methylphenoxy)-2-phenoxy-Δ³-1,3,4-oxadiazoline 
• 452336-02-6 2-(o-iodophenoxy)-2-phenoxy-5,5-dimethyl-Δ³-1,3,4-oxadiazoline 
• 198778-00-6 9-Benzenesulfonyl-3,3-dimethyl-4,6-dioxa-1,2,9-triaza-spiro[4.4]non-1-ene 
• 92573-96-1 2-methoxy-5,5-dimethyl-2-phenyl-Δ³-1,3,4-oxadiazoline 
• 119393-21-4 2-cyclopropyl-2-methoxy-5,5-dimethyl-Δ³-1,3,4-oxadiazoline 
• 77879-49-3 2-Methoxy-2,5,5-trimethyl-Δ³-1,3,4-oxadiazoline 
• 947-57-9 dimethyl bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylate 

Relevant articles and documents

Ortho substituent effects on transfer of aryl groups from oxygen to carbon in adducts from diaryloxycarbenes and DMAD

Diaryloxycarbenes, generated by thermolysis of 2,2-diaryloxy-5,5-dimethyl-Δ3-1,3,4-oxadiazolines in benzene, reacted with dimethyl acetylenedicarboxylate (DMAD) to afford triesters. The triesters arose by aryl-group transfer from oxygen to carb

Chemistry of cyclic aminooxycarbenes

A series of oxazolidin-2-ylidenes and one tetrahydro-1,3-oxazin-2-ylidene, generated by thermolysis of Δ3-1,3,4-oxadiazolines in benzene at 90 °C, were intercepted by insertion into the OH bond of phenols. In two cases the initial products rearranged to N-(2-aryloxyethyl)-N-methylformamides. The activation energy for rotation about the amide CN bond of those ultimate products was measured as 20.4 kcal/mol. The aminooxycarbenes reacted with two equivalents of methyl or phenyl isocyanate to give spiro-fused hydantoins. Major products from the reactions of the N-carbonyl carbenes with dimethyl acetylenedicarboxylate or with methyl propiolate were 2-oxazolines resulting from apparent acyl transfers from N to C in the proposed dipolar intermediates; minor products of 1:2 (carbene:trap) stoichiometry were also observed.

SITE SELECTIVITY IN THE REACTIONS OF 1,3-DIPOLES WITH NORBORNADIENE DERIVATIVES

The cycloadditions of arylazides, benzonitrile oxides and diphenylnitrile imine to norbornadiene derivatives 1a-c showed varying degree of site- and stereo-selectivity.With dipolarophile 1a arylazides and benzonitrile oxides attack, preferentially, the electron-poor tetrasubstituted double bond, while in the case of 1b and 1c is the substituted double bond which enters the cycloaddition.By contrast, 2-diazopropane and C-phenyl-N-methylnitrone react with the sole tetrasubstituted double bond of 1a-c in stereo- and site-specific cycloadditions.The quantitative evaluation of the two possible reaction paths was performed by glc analysis.The compounds detected were those arising from Diels-Alder cycloreversions of the thermally labile intermediate adducts 2 and 3 (Scheme 1).The results were rationalized on the basis of a qualitative perturbation treatment which considers frontier orbital interactions only.