Ethyl 2-(Bromomethyl)acrylate

(R = Et) [17435-72-2] C6H9BrO2 (MW 193.04) InChI = 1S/C6H9BrO2/c1-3-9-6(8)5(2)4-7/h2-4H2,1H3 InChIKey = MTCMFVTVXAOHNQ-UHFFFAOYSA-N (R = tert-Bu) [53913-96-5] C8H13BrO2 (MW 221.09) InChI = 1S/C8H13BrO2/c1-6(5-9)7(10)11-8(2,3)4/h1,5H2,2-4H3 InChIKey = AEZPDFMFNUKVCF-UHFFFAOYSA-N (powerful allylic alkylating reagent,1-3 reacts as an electrophile with various organometallic compounds; employed as its organozinc derivative to prepare α-methylene lactones4 and lactams;5 important source of functional acrylic monomers for polymerization; powerful alkylating agent, used as its organometallic derivatives to prepare α-methylene lactones and lactams; source for allyl radicals; important source of functionalized acrylic monomers for polymerization6-8) Alternate Name: ethyl 2-(bromomethyl)propenoate. 2-(Bromomethyl)-2-propenoic acid ethyl ester. Physical Data12: R = Et, bp 40–41 °C/0.1 mmHg; R = tert-Bu, bp 60–61 °C/0.1 mmHg. bp 86 °C/ 20 mm Hg; nD20 = 1.4800. Solubility: insol H2O; sol ether, acetone, alcohol, THF, chloroform. Form Supplied in: colorless liquid. Preparative Methods: many preparations of these compounds have been described,9 for example dehydrobromination of β,β′-dibromoisobutyric esters10-12 or acid, or bromination of tert-butyl or Ethyl α‐(Hydroxymethyl)acrylate with Phosphorus(III) Bromide.13 Ethyl 2-(bromomethyl)acrylate can be prepared most conveniently by a Wittig-Horner reaction and subsequent bromination (eq 1).13 (1) Alternative methods starting from malonates and formaldehyde have been reported. Upon treatment with hydrobromic acid, the resulting diol undergoes bromination, saponification and decarboxylation. Elimination occurs at elevated temperature whereas the reaction at ambient temperature necessitates dehydrobromination with triethylamine (eq 2). (2) Handling, Storage, and Precautions: reputed to be lachrymatory, vesicatory, and toxic. Usual precautions of storage in darkness between 0 and 5 °C and handling with gloves under a well ventilated hood are recommended.