19859-29-1

Basic information

• Product Name: 2-(methylselanyl)-1-phenylethan-1-one
• Synonyms: 2-(methylselanyl)-1-phenylethan-1-one
• CAS NO: 19859-29-1
• Molecular Weight: 213.138
• Mol File: 19859-29-1.mol
• Article Data: 5

Chemical Properties

• CAS DataBase Reference: 2-(methylselanyl)-1-phenylethan-1-one(CAS DataBase Reference)
• NIST Chemistry Reference: 2-(methylselanyl)-1-phenylethan-1-one(19859-29-1)
• EPA Substance Registry System: 2-(methylselanyl)-1-phenylethan-1-one(19859-29-1)

Safety Data

• Hazardous Substances Data: 19859-29-1(Hazardous Substances Data)

Upstream product

• 186581-53-3 diazomethane 
• 5925-66-6 methyl benzoselenoate 
• 19320-74-2 Se-phenacyldimethylselenonium bromide 
• 603-35-0 triphenylphosphine 
• 100-42-5 styrene 
• 7101-31-7 dimethyl diselenide 
• 6919-61-5 N-methoxy-N-methylbenzamide 
• 56051-03-7 bis(methylseleno)-methane 
• 70392-74-4 dimethylphenacylselenonium tetraphenylborate 

Relevant articles and documents

Expeditious and Chemoselective Synthesis of α-Aryl and α-Alkyl Selenomethylketones via Homologation Chemistry

Diselenoacetals, previously considered byproducts in homologation tactics en route to α-selenoketones, are herein found to be excellent starting materials for this purpose. The easy selenium/lithium exchange they undergo affords seleno carbanions which are smoothly added to Weinreb amides to chemoselectively prepare α-aryl- and α-alkyl seleno methylketones through a single chemical operation. No racemization events are observed in the presence of optically pure starting materials.

REACTION OF DIAZOMETHANE WITH SELENOESTERS PREPARATION OF α-(ALKYL- OR ARYLSELENO)METHYL KETONES AND METHYL KETONES

The reaction of diazomethane with a series of selenoesters 1 in the presence of CuI, CuSePh or Cu powder produced α-(alkyl- or arylseleno)methyl ketones 2 in yield of 41-65percent.Methyl ketones 3 and bis(arylseleno)methanes 9 or 14 were formed as by-products.The direct conversion of selenoesters to methyl ketones was accomplished in high yield by the usual reaction with diazomethane, followed by workup with HBr solution.The simultaneous copper-catalyzed reactions of selenoesters 1c and 1i with diazomethane resulted in crossover, with the formation of all four possible α-seleno ketones 2b, 2c, 2h and 2i.A non-concerted mechanism involving attack by the diazo compound upon the acyl carbon atom of an activated selenoester with the formation of a tetrahedral intermediate 11 has been suggested.The reaction of the selenothiocarbamate 4 with diazomethane resulted in 1,3-dipolar cycloaddition to afford 5 instead of insertion into the acyl-selenium bond.

REACTION OF ARACYL- AND ALKOXYCARBONYLMETHYLSELENONIUM SALTS WITH NUCLEOPHILIC REAGENTS

A method is proposed for the synthesis of α-methylselenium derivatives of aryl and heteryl methyl ketones and ethyl acetate by demethylation of readily available aracyl-, heteroacyl-, and methoxycarbonylmethylselenonium salts with triethylamine.It was established that triphenylphosphine cleaves dimethylphenacylselenonium bromide both at the Se-methyl and at the Se-CH2COPh bond (preferentially).Triphenylphosphine selenide is formed in this reaction in addition to the corresponding phosphonium salts.