72722-52-2

Upstream product

• 17343-73-6 (2,2-dibromo-1-methylcyclopropyl)benzene 
• 65051-83-4 3-methyl-3-phenylcyclopropene 

Downstream Products

• 29161-89-5 2-methyl-2-phenylcyclopropanecarboxylic acid 
• 29161-89-5 trans-2-methyl-2-phenylcyclopropanecarboxylic acid 

Relevant academic research and scientific papers

Functionalized α-bromocyclopropylmagnesium bromides: Generation and some reactions

Functional derivatives of gem-dibromocyclopropanes (ethers and esters of gemdibromocyclopropylmethanol, 2,2-dibromocyclopropanecarboxylic acids and their esters) undergo partial hydrodebromination at the treatment with isopropyl magnesium bromide (3-6 mol-equiv) in THF and then in methanol at -60°C affording the corresponding monobromides in 64-95% yields. The addition of nonsolvated magnesium bromide to the reaction mixture results in the considerable reduction of the amount of the Grignard reagent (from 6 to 3 mol-equiv). This allows achieving the partial hydrodebromination of 2,2-dibromocyclopropanecarboxylic acids. Pleiades Publishing, Ltd., 2013.

Highly diastereo- and regioselective transition metal-catalyzed additions of metal hydrides and bimetallic species to cyclopropenes: Easy access to multisubstituted cyclopropanes

(Chemical Equation Presented) The first highly efficient, diastereo- and regioselective transition metal-catalyzed addition of metal hydrides (stannanes, silanes, and germanes) and bimetallic species (ditins and silyltins) to cyclopropenes has been develo

Oxidation of organometallic compounds (RM, M = Li, MgBr, ZnBr, CuCNLi, Cu(R)CNLi2) with tBuOOLi, Ti(OiPr)4-mediated with tBuOOH, and with O2, to give alcohols (ROH). Are radicals R? involved?

Organometallic compounds (RM, M = Li, MgBr, ZnBr, Cu(CN)Li, CuR(CN)Li2) are oxidized with tBuOOLi (or PhCMe2OOLi) (method A) to the corresponding alcohols (ROH), in good to very good yields. This oxidation works also well with the protic system Ti(OiPr)4 + tBuOOH (method B) in the case of RM, M = Li, MgBr and ZnBr. Stereochemical studies with the configurationally stable cis- and trans-cyclopropyl metal compounds, cis- and trans-1-M, respectively, show that the reactions of RM, M = Li, MgBr, with tBuOOLi (method A) and Ti(OiPr)4 + tBuOOH (method B) follow a SN2-type pathway of the nucleophile RM at the electrophilic (although anionic!) oxygen atom of tBuOOLi(TiX3) to give ROM (isolated as the esters 2) with retention of configuration at R. In contrast, the oxidations with dioxygen O2 (method C) occur with loss of stereochemistry in the cyclopropyl alcohols ROH (RM, M = Li, MgBr), and additional formation of cyclopropyl dimers R-R 3 in the case of RM, M = Cu(CN)Li, CuR(CN)Li2. This is due to facile electron transfer from RM to O2 and fast isomerization (dimerization) of the intermediate radicals R?. The high tendency of RM cuprates, M = Cu(CN)Li, CuR(CN)Li2, for electron transfer reactions is also indicated by some loss of stereospecificity in the formation of ROH, and some dimer 3 formation, even with the oxidant tBuOOLi (method A) .

Hydrodehalogenation of 1,1-dibromocyclopropanes by Grignard reagents promoted by titanium compounds

1,1-Dibromocyclopropanes are converted into the corresponding monobromocyclopropanes (as mixtures of stereoisomers where appropriate) by reaction with 1.0-1.3 mol equiv. of ethylmagnesium bromide and 2-10 mol% titanium isopropoxide for 90%). With ethylmagnesium bromide, the reaction occurs very slowly in the absence of catalyst; with methylmagnesium bromide, the reaction does occur in the absence of catalyst, but is only slightly promoted in the presence of titanium isopropoxide. Reactions with a number of other Grignard reagents are also discussed. In the case of phenethylmagnesium bromide, the major product containing the phenethyl-group is ethylbenzene, together with small amounts of styrene and ethyl 4-phenyl-2-butyl ether, a product of trapping of the solvent, ether. In other cases, relatively large amounts of a diether, formally derived by hydrogen ion adjacent to the ether oxygen followed by dimerisation, are isolated. No products were identified incorporating the cyclopropane and either the Grignard alkyl group or the solvent. Labelling studies indicate that the hydrogen introduced into the cyclopropane is not derived from either the α- or β-positions of the Grignard reagent. When the reduction is carried out with phenethylmagnesium bromide in d8-tetrahydrofuran both monobromides contain deuterium.

Reduction of geminal dihalocyclopropanes with ethylmagnesium bromide in the presence of tetraisopropoxytitanium

Reactions of geminal dichloro(dibromo)cyclopropanes with excess ethylmagnesium bromide in the presence of tetraisopropoxytitanium as catalyst lead to the corresponding stereoisomeric monohalocyclopropanes in good yields. A mechanism is proposed which invo

A simple and efficient hydrodehalogenation of 1,1-dihalocyclopropanes

1,1-Dibromo- and 1,1-dichlorocyclopropanes are converted into the corresponding monohalocyclopropanes (as mixtures of stereoisomers where appropriate) by reaction with 1.2-1.3 mol. equiv. of ethyl magnesium bromide and a small amount of titanium isopropoxide in ether. In the presence of an excess of ethylmagnesium bromide the product from the dibromide is the non- halogenated cyclopropane. Copyright (C) 1996 Elsevier Science Ltd.

ELECTROCHEMICAL REDUCTION OF 1,1-DIHALO-2,2-DISUBSTITUTED CYCLOPROPANES

The electrochemical reduction of 1,1-dihalo-2-R-2-methylcyclopropanes was studied by polarography and preparative electrolysis.A mixture of stereoisomeric monobromo- and monochlorocyclopropanes was obtained with preparative yield of 60-70percent in prepar