54945-11-8

Basic information

• Product Name: 1,3-DIMETHYL-5-PYRAZOLIDONE
• Synonyms: 1,3-DIMETHYL-5-PYRAZOLIDONE
• CAS NO: 54945-11-8
• Molecular Formula: C5H10N2O
• Molecular Weight: 114.15
• Mol File: 54945-11-8.mol
• Article Data: 2

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 1,3-DIMETHYL-5-PYRAZOLIDONE(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3-DIMETHYL-5-PYRAZOLIDONE(54945-11-8)
• EPA Substance Registry System: 1,3-DIMETHYL-5-PYRAZOLIDONE(54945-11-8)

Safety Data

• Hazardous Substances Data: 54945-11-8(Hazardous Substances Data)

Usage

General Description

1,3-Dimethyl-5-pyrazolidone, also known as DMPU, is a cyclic tertiary amide with the molecular formula C6H12N2O. As a specialty solvent, it has applications in organic chemistry for increasing the reactivity of certain reagents and acting as a base. While it is less frequently used than its analogs such as 1,3-dimethyl-2-imidazolidinone (DMI) or hexamethylphosphoramide (HMPA), it has a greater solvating power for ionics, leading to better yield in reactions. The compound has a potential risk of skin and eye irritation, and NIH's PubChem lists it as potentially harmful if swallowed, inhaled or absorbed through the skin.

Upstream product

• 204197-22-8 (RS)-tert-butyl 2,5-dimethyl-3-oxopyrazolidine-1-carboxylate 
• 623-43-8 crotonic acid methyl ester 
• 60-34-4 methylhydrazine 

Relevant articles and documents

Development of Scalable Processes for the Preparation of N-Methyl-3-Bromo-5-Methyl Pyrazole

The development and optimization of two scalable routes to N-methyl-3-bromo-5-methyl pyrazole is described. The initial Sandmeyer route entailed a three-step sequence from crotonitrile and methyl hydrazine, proceeding through the 3-amino pyrazole intermediate. Due to the GTI liability of the 3-amino pyrazole intermediate, a tedious steam-distillation, and 30% overall yield, we developed a second-generation Sandmeyer-free approach from methyl crotonate and methyl hydrazine which leveraged a condensation, bromination, and oxidation sequence. Process development led to the improved preparation of N-methyl-3-bromo-5-methyl pyrazole with increased efficiency and overall yield. The isolation, handling, and storage of the final product was greatly improved through the generation of the triflic acid salt, and salt form studies are also discussed.