[10029-04-6] · C6H10O3 · Ethyl a-(Hydroxymethyl)acrylate · (MW 130.16)
(important source of functionalized acrylic monomers for polymerization and copolymerization; intermediate in the preparation of a-(halomethyl)acrylates, methacrylates, and a-methylene lactones; powerful polyfunctional Michael acceptor)
Physical Data: bp 65-70 °C/1 mmHg; n
Solubility: sol H2O, ether, acetone, alcohol, THF, chloroform.
Preparative Methods: by hydroxymethylation of Ethyl Acrylate with aqueous Formaldehyde solution in the presence of tertiary amines (Triethylamine, 1,4-Diazabicyclo[2.2.2]octane),3 under microwave radiation,4 or by the Wittig-Horner reaction of Triethyl Phosphonoacetate with formaldehyde in the presence of aqueous Potassium Carbonate (eq 1).5,6 Many side reactions have been found to occur with the first method and the mechanism involving the formation of ethers has been elucidated.7 Carbonylation of propargyl alcohol to produce this reagent has also been described.8
Purification: by distillation at reduced pressure.
Analysis of Reagent Purity: by GLC analysis (e.g. 2 m silica capillary OV-1 column); 1H NMR (CCl4) 4.20 (2H), 5.80 and 6.15 (2H); 13C NMR (CDCl3) 60.9, 124.8, 140.2, and 166.5.
Handling, Storage, and Precautions: is lachrymatory, vesicatory, and toxic.2 This reagent should be handled with gloves in a well ventilated hood. Storage at 0 °C in the dark is recommended.
Ethyl a-(hydroxymethyl)acrylate has been fully studied for polymerization as the pure compound,9,10 as its derivatives (chloride,11 trityl,12 acetoxy,13 disilyloxy14), as difunctional and multifunctional monomers capable of cyclopolymerization15 and copolymerization with 2-vinyl-4,4-dimethylazlactone,16 or as crosslinking agents with biepoxides.17 It has found employment for the impregnation and in-situ polymerization in the manufacture of wood-polymer composites.18
The corresponding bromide and chloride11 have been prepared by reaction of ethyl a-(hydroxymethyl)acrylate with Phosphorus(III) Bromide and Thionyl Chloride,5 while the fluoride and iodide have been obtained by halogen exchange.5
a-(Hydroxymethyl)acrylate can act as a Michael acceptor and, in this way, it can add magnesium organocuprates without subsequent elimination giving rise to a-(hydroxymethyl)alkanoic esters (eq 2). In contrast, reaction of the acetoxy derivative with Grignard reagents in the presence of a catalytic amount of CuI salt leads to the formation of a-substituted acrylic esters (eq 3).19
Palladium-catalyzed hydroxyalkylation of aldehydes and cyclohexanone by a-(hydroxymethyl)acrylate derivatives in the presence of Tin(II) Chloride and 1,3-Dimethyl-2-imidazolidinone (DMI/H2O) was shown to be a new route to a-methylene-g-butyrolactones (eq 4).20
A new synthesis of a-(1-hydroxyalkyl)-b-lactams21 by addition of primary amines to ethyl a-(hydroxymethyl)acrylate has been recently proposed (eq 5).
Bromine addition-dehydrobromination on ethyl a-(hydroxymethyl)acrylate resulted in the formation of a-(bromomethyl)glycidic ester (eq 6).22
Ethyl a-(hydroxymethyl)acrylate was also employed as allyloxycarbonyl protecting group for amino acids in peptide synthesis23 and used as an intermediate in the total synthesis of (±)-heptelidic acid.24
Jean Villieras & Monique Villieras
University of Nantes, France