118987-41-0

Basic information

• Product Name: 2-Azetidinone, 3-acetyl-4-ethylidene-1,3-dimethyl-, (E)- (9CI)
• Synonyms: 2-Azetidinone, 3-acetyl-4-ethylidene-1,3-dimethyl-, (E)- (9CI)
• CAS NO: 118987-41-0
• Molecular Formula: C9H13NO2
• Molecular Weight: 167.20502
• Product Categories: ACETYLGROUP
• Mol File: 118987-41-0.mol
• Article Data: 1

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 2-Azetidinone, 3-acetyl-4-ethylidene-1,3-dimethyl-, (E)- (9CI)(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Azetidinone, 3-acetyl-4-ethylidene-1,3-dimethyl-, (E)- (9CI)(118987-41-0)
• EPA Substance Registry System: 2-Azetidinone, 3-acetyl-4-ethylidene-1,3-dimethyl-, (E)- (9CI)(118987-41-0)

Safety Data

• Hazardous Substances Data: 118987-41-0(Hazardous Substances Data)

Usage

Classification

Azetidinone

Azetidinone

Organic compounds containing a four-membered azetidine ring

Functional Groups

Acetyl group: \textCOCH3
Ethylidene group: \textCH3\textCH=\textCH2
Two methyl groups: \textCH3

Configuration

(E)indicates the ethylidene group is in the E configuration

E Configuration

The two substituent groups on the double bond are on opposite sides of the bond

Applications

Used in the synthesis of pharmaceuticals and other organic compounds

Upstream product

• 118987-34-1 4-acetoxy-3-acetyl-4-ethyl-1,3-dimethylazetidin-2-one 
• 118987-29-4 2-ethyl-3,5,6-trimethylpyrimidin-4(3H)-one 

Relevant articles and documents

Photochemistry of 5-methylpyrimidin-4-ones in acetic acid solution: Thermal rearrangements of Dewar pyrimidinones and 4-acetoxyazetidin-2-ones

Irradiation of 3,6-dialkyl-5-methylpyrimidin-4-ones (1a-f) in acetic acid-acetonitrile (1:2, v/v) solution at 0 °C gave 4-acetoxy-3-(1-imino-2,2- dimethylpropyl)-1,3,4-trimethylazetidin-2-one (3a), 6-acetoxy-7-(1-imino-2,2- dimethylpropyl)-7-methyl-1-azabicyclo[4.2.0]octan-8-one (3b), 4-acetoxy-3-acetyl-1,3,4-trialkylazetidin-2-ones (4c-e), 4-acetoxy-3-acetyl-1,3- dimethylazetidin-2-one (4f), 3-acetyl-4-alkylidene-1,3-dimethylazetidin-2-ones (5d) and (5e) as the major products. Reaction of 1,4,6-trimethyl-3-t-butyl-2,6- diazabicyclo[2.2.0]hex-2-en-5-one (2a) (Dewar pyrimidinone) in acetic acid-acetonitrile (1:14, v/v) solution at 0 °C and thermolysis of (2a) without solvent at 80 °C gave the imine azetidin-2-one (3a) and 2,3,5-trimethyl-6-t-butylpyrimidin-4(3H)-one (1a) respectively as the major products. Reactions of the imino azetidin-2-ones (3a) and (3b) and the 4-acetoxyazetidin-2-ones (4c-e) in the presence of acetic acid at 21-40 °C and without solvent at 100-110 °C were carried out to elucidate the rearrangements. The major products from (3a) and (3b) in acidic solutions at 40 °C were N-acetyl-3-acetamido-2,4,4,N-tetramethylpent-2-enamide (6a), N-methylacetamide (9a), 2,5-dimethyl-4-t-butyl-1,3-oxazin-6-one (10a), 2-piperidone (9b), and 1,3-oxazin-6-one (10b) = (10a), and from the thermolysis of (3a) and (3b) at 100-110 °C were the pyrimidin-4-ones (1a) and (1b), 1,3-dimethyl-3-pivaloyl-4-vinylazetidin-2-one (5a) and 7-methyl-7-pivaloyl-1- azabicyclo[4.2.0]octa-5-en-8-one (5b). Both reactions of (4d,e) at 23-24 °C in acidic solutions and of (4c,d) without solvent at 100-110 °C gave the 3-acetyl-4-alkylidene-1,3-dimethylazetidin-2-ones (5c-e) as the major products. The reaction mechanisms and intermediates of these reactions are discussed.