- Electrocatalytic Radical Dichlorination of Alkenes with Nucleophilic Chlorine Sources
-
We report a Mn-catalyzed electrochemical dichlorination of alkenes with MgCl2 as the chlorine source. This method provides operationally simple, sustainable, and efficient access to a variety of vicinally dichlorinated compounds. In particular, alkenes with oxidatively labile functional groups, such as alcohols, aldehydes, sulfides, and amines, were transformed into the desired vicinal dichlorides with high chemoselectivity. Mechanistic data are consistent with metal-mediated Cl atom transfer as the predominant pathway enabling dual C-Cl bond formation and contradict an alternative pathway involving electrochemical evolution of chlorine gas followed by Cl2-mediated electrophilic dichlorination.
- Fu, Niankai,Sauer, Gregory S.,Lin, Song
-
supporting information
p. 15548 - 15553
(2017/11/06)
-
- Synthesis of chloro alkoxy and alkoxy derivatives of methyl oleate
-
Vegetable oil based lubricants typically have improved lubricity and biodegradability over their mineral oil based counterparts. However, vegetable oil lubricants often fail to meet the performance standards of mineral based oils with respect to cold temperature and resistance to oxidation. Olefins are an oxidatively weak point for vegetable based compounds. Removal of the olefin in a vegetable based lubricant through functionalization may increase resistance to oxidation. If the added functionality also causes branching of the alkyl chain, cold temperature properties may be improved. Any chemical modifications considered must be scalable and cost-effective to be useful in a commercial application. In this study, methyl oleate was functionalized into a chloro alkoxy derivative. Sodium hypochlorite (household bleach) and calcium hypochlorite were both used to generate hypochlorous acid in situ. Hypochlorous acid and a series of alcohols (methanol, ethanol, and butanol) were reacted with methyl oleate to make chloro alkoxy compounds in 29.8-77.9 % yields. In an effort to make a branched saturated ether we removed the chlorine moiety of the chloro alkoxy compounds. Dehalogenation was achieved under basic conditions over a Pd/C catalyst in 2-propanol. Reaction times increased substantially as the size of the adjacent alkoxy group increased. The reaction rate could be improved by heating the reactions above 100 C in a pressure reactor. Increased reaction temperature also resulted in an increase in ketone side products from the competing elimination reactions. Saturated ether yields were 4.1-43.2 %.
- Lowery, Benjamin A.,Andersh, Brad,Isbell, Terry A.
-
p. 911 - 917
(2013/07/27)
-
- Organic halogen compounds, EOX, in mussels from a clean lake and a pulp mill recipient
-
The extractable organic halogen (EOX) residue of duck mussels, Anodonta anatina, from the unpolluted Lake Hoytiainen, Finland, was found to be 690 μg/g of lipids. The residue was characterized by analyzing chlorinated phenols, hydrocarbons and fatty acids. These compound classes accounted only for 1.9% of the EOX. Mussels from the same lake were incubated in a lake receiving pulp and paper mill effluents for 12 months to study the bioaccumulation of organochlorine compounds. The EOX of these mussels was 2045 μg/g lipids and only 1.1% of the residue was explained by the low molecular weight compounds. Thus, the majority of EOX remains undefined. However, potential differences in composition are suggested by the relative proportion of defined compounds and the differences among the measured compound classes. These halogen compounds may be of natural origin or reaction products of anthropogenic compounds with humic substances. The presence of such compounds should be taken into account when evaluating the accumulation of pulp mill effluent-related EOX in mussels. No difference was found in the EOX between male and female mussels caged close to a pulp mill, but, on dry weight basis, mussels infected by a digenean parasite had higher EOX concentration than healthy females.
- Pellinen, Jukka,Ruokolainen, Minna,Maekelae, Petteri,Taskinen, Jouni
-
p. 1515 - 1526
(2007/10/03)
-