Dimethyl Dicarbonate

Sold under the trade name Velcorin, the sterilant dimethyl dicarbonate (DMDC) is approved for use in the United States for table as well as 

The antimicrobial effect of DMDG results from inactivation of microbial enzymes (Ough, 1993a). Porter and Ough (1982) reported the 

Adapted from Ough (1993a) and J. Just (personnal communication, 

Another concern regarding the use of Velcorin is safety. This chemical is toxic by ingestion and inhalation, is a skin and eye irritant, and is combustible when exposed to an open flame. As such, safety precautions must be taken when using Velcorin in a winery. The dosing equipment does reduce safety risks given the toxicity of the chemical. 

---

Ketones can also be prepared directly from carboxylic acids by activation as mixed anhydrides by dimethyl dicarbonate.236 These conditions were used successfully with alkanoic and alkanedioic acids, was well as aromatic acids. 

Development and validation of procedures to detect and quantify the use of dimethyl dicarbonate in nonalcoholic drinks. 

To confirm the rapid degradation of DMDC (dimethyl dicarbonate) (E242) in nonalcoholic drinks and to develop and validate methods of analysis for the detection and quantification of the use of the sterilant. 

Annex III lays down the conditions of use for permitted preservatives and antioxidants, with lists of foods and maximum levels in each case. Part A lists the sorbates, benzoates and p-hydroxybenzoates, E 200-E 219 part B lists sulphur dioxide and the sulphites, E 220-E 228 part C lists other preservatives with their uses, including nisin, dimethyl dicarbonate and substances allowed for surface treatment of certain fruits, E 249 potassium nitrite, E 250 sodium nitrite, E 251 sodium nitrate and E 252 potassium nitrate, E 280-E 283 propionic acid and the propionates part D lists the antioxidants E 320 butylated hydroxyanisole (BHA), E 321 butylated hydroxytoluene (BHT), E 310 propyl gallate, E 311 octyl gallate, E 312 dodecyl gallate, E 315 eiythorbic acid and E 316 sodium erythorbate. 

Dimethyl Dicarbonate occurs as a clear, colorless liquid. Its solubility in water is 35 g/L at 20° with decomposition, its melting point is about 17°, and its flash point is 85°. It reacts quantitatively with water, producing carbon dioxide and methanol. 

Caution Dimethyl Dicarbonate is toxic if inhaled. Function Preservative antimicrobial. 

Procedure Transfer about 2 g of sample, accurately weighed, into a 250-mL beaker, and dissolve it in 100 mL of acetone. Add 25 mL of 1 N Di-n-butylamine by pipet, allow the mixture to stand for 5 min, and titrate with 1 N hydrochloric acid, determining the endpoint potentiomet-rically. Perform a blank titration (see General Provisions), and make any necessary correction. Calculate the percent Dimethyl Dicarbonate in the sample taken by the formula... 

Calcium Lignosulfonate beta-Cyclodextrin Dimethyl Dicarbonate Glyceryl Palmitostearate 4-Hexylresorcinol Magnesium Phosphate, Dibasic, Mixed Hydrates Manganese Citrate Olestra... 

E239 Hexamethylene tetramine E242 Dimethyl dicarbonate... 

Eurther application of the processes in Eqs. 1.8 and 1.9 led to syntheses of various aldehydes and ketones directly from carboxylic acids with use of an activator such as pivalic anhydride and dimethyl dicarbonate (Eqs. 1.10 and 1.11) [35,38]. 

The acylpalladium 141 is formed by oxidative addition of acid anhydride to Pd(0), and can be used for synthetic purposes [61]. The mixed anhydride 143 was prepared in situ by the reaction of benzoic acid with dimethyl dicarbonate (142), and the benzoylpalladium methoxide 144 is generated by decarboxylative oxidative addition of 143, and is used for Suzuki coupling with arylboronic acid to yield the diaryl ketone 145 [62]. 

Dimethyl-S-(1,2-dicarbethoxyethyl) dithiophosphate. See Malathion 0,0-Dimethyl-S-(1,2-dicarbethoxy) ethyl phosphorothioate. See Malaoxon Dimethyl dicarbonate CAS 4525-33-1 EINECS/ELINCS 224-859-8 INS242 E242... 

DMDA-6500. See Polyethylene, high-density DMDC. See Dimethyl dicarbonate DMDC-6400 Natural 7, DMDC-6400, DMDD-6400 Natural 7, DMDD-640a, DMDD-6500 Natural 7. See Polyethylene, high-density DM DEE. See Bis (2-morpholinoethyl) ether... 

Beeswax, white Beeswax, yellow Benzoic, acid Benzyl tiglate y-Bisabolene Brominated vegetable oil 3-Butylidenephthalide Butyloxepanone 3-Butylphthalide Calcium lactate Caramel Castor (Ricinus communis) oil Citronellyl isovalerate Citronellyloxy acetaldehyde p-Cresyl isovalerate p-Cresyl octanoate Crotonic acid p-Cyclocitral p-Damascenone 9-Decenal trans-4-Decenal Diacetyl tartaric acid esters of mono- and diglycerides Diethyl malate Difurfuryl disulfide Dihydroeugenol Dihydro-a-ionone Dihydrojasmone Diisobutyl ketone Diisopropyl disulfide 3,4-Dimethylcyclopentane-1,2-dione Dimethyl dicarbonate 2,5 Dimethyl-3-furanthiol p-a-Dimethylstyrene Diphenyl oxide Ethyl acetate... 

Carbon monoxide Hydrogen Methane gas methionine synthesis Methyl mercaptan methoxycarbonylating agent Dimethyl dicarbonate methyl alcohol mfg. 

Coriander (Coriandrum sativum) oil Cupric sulfate anhydrous Dehydroacetic acid Dimethyl dicarbonate Disodium EDTA Edetic acid Erythorbic acid Ethyl vanillate Ferulic acid Formic acid Fructose Fumaric acid Glucose oxidase Guaiac gum Heptyl paraben Hexamethylenetetramine 4-Hydroxymethyl-2,6-di-t-butylphenol Isobutylparaben Isopropyl citrate Isopropylparaben Lactic acid Methyl paraben Myristalkonium chloride Natamycin Nisin o-Phenylphenol Potassium acetate Potassium bisulfite Potassium butyl paraben Potassium diacetate... 

Dimethyl dicarbonate Potassium sorbate Sodium sulfite preservative, wood... 

Dimethyl dicarbonate 4536-30-5 Alkasurf LAN-1 BIO-SOFT E-200 Hetoxol L-1 Laureth-1 Lipocol L-1 Nikkol BL-1SY Rhodasurf LAN-1 4548-53-2 Cl 14700 FD C Red No. 4 Ponceau SX 4553-89-3 Brown HT 4560-68-3 Citmol 316 Triisocetyl citrate 4568-28-9 Arlypon V 600 TEA-stearate 4572-09-2... 

Dimethyl dicarbonate N-Hydroxysuccinic acid C4H6O6 Pb Lead maleate, tribasic C4H6O6 D-Tartaric acid DL-Tartaric acid L-Tartaric acid C4H7AIN4O5 Aldioxa C4H7AIO5... 

Furthermore, in 1998 Ube Industries, Ltd. expanded their research from doublebond compounds to triple-bond compounds and discovered that alkyne compounds such as methyl propargyl carbonate (13), propargyl acetate (14), and 2-butyne-l,4-diol dimethyl dicarbonate (15) suppress the decomposition of PC [53]. In 1999, the same company discovered that a mixture of methyl propargyl carbonate (13) and VC is capable of improving battery performance even further [27, 54]. 

---