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Upstream product

• 156-60-5 trans-1,2-dichloroethylene 
• 110-82-7 cyclohexane 
• 156-59-2 cis-1,2-Dichloroethylene 
• 28540-81-0 (E) 2-iodo-1-chloroethylene 
• 26620-11-1 (E)-2-chlorovinylthiobenzene 
• 38238-75-4 (E)-2-chloroethenyl phenyl sulfone 
• 75-47-8 iodoform 
• 2043-61-0 cyclohexanecarbaldehyde 
• 24371-94-6 cyclohexylmercury chloride 
• 1190-78-9 cis-2-chloro-vinylmercury ⁽¹⁺⁾; chloride 
• 1190-78-9 trans-β-chlorovinylmercury chloride 
• 1026713-51-8 2-bromo-2-chloro-1-cyclohexyl-ethanol 
• 247943-54-0 2-bromo-2-chloro-1-cyclohexylethyl acetate 
• 695-12-5 vinylcyclohexane 

Relevant academic research and scientific papers

Kinetically controlled E-selective catalytic olefin metathesis

A major shortcoming in olefin metathesis, a chemical process that is central to research in several branches of chemistry, is the lack of efficient methods that kinetically favor E isomers in the product distribution. Here we show that kinetically E-selective cross-metathesis reactions may be designed to generate thermodynamically disfavored alkenyl chlorides and fluorides in high yield and with exceptional stereoselectivity.With 1.0 to 5.0 mole % of a molybdenum-based catalyst, which may be delivered in the form of air- and moisture-stable paraffin pellets, reactions typically proceed to completion within 4 hours at ambient temperature. Many isomerically pure E-alkenyl chlorides, applicable to catalytic cross-coupling transformations and found in biologically active entities, thus become easily and directly accessible. Similarly, E-alkenyl fluorides can be synthesized from simpler compounds or more complex molecules.

Synthesis of (E)-α,β-unsaturated esters and (Z)-vinyl halides with total or high diastereoselectivity by using samarium metal

A highly diastereoselective β-elimination of 2-halo-3-hydroxy esters 1 or O-acetylated 1,1-dihaloalkan-2-ols 4 is achieved with samarium in the presence of diiodomethane, yielding α,β-unsaturated esters 2 or vinyl halides 5, respectively. The β-elimination reaction was promoted by samarium diiodide, which was generated in situ. The starting halohydrins 1 or 4 are easily prepared by reaction of the corresponding lithium enolates of α-halo esters or dihalomethyllithium with aldehydes at -78°C. The influence of the reaction conditions and the structure of the starting compounds on the diastereoselectivity of the β-elimination reactions is discussed, A comparative study of the β-elimination reaction with preformed SmI2 and metallic samarium is also performed. These elimination reactions can be explained by the proposed mechanism. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002).

A practical transformation of aldehydes into (E)-iodoalkenes with geminal dichromium reagents

A catalytic cycle of a chromium salt in a stereoselective transformation of aldehydes to (E)-l-iodoalkenes using a geminal dichromium reagent, is assembled with zinc, Me3SiCl, and NaI in dioxane.

Samarium-mediated β-elimination in dihalo alcohols: Diastereoselective synthesis of (Z)-vinyl halides

High diastereoselectivity in β-elimination reactions of O-acetyl 1,1- dihaloalkan-2-ols to give (Z)-vinyl halides was achieved by using samarium diiodide [Eq. (1)]. The reaction was also highly diastereoselective and totally chemoselective when a mixture

Electron-transfer processes. 43. Attack of alkyl radicals upon 1-alkenyl and 1-alkynyl derivatives of tin and mercury

Alkyl radicals, obtained by reaction of Bu3Sn? or ClHg? with alkylmercury halides, will undergo regioselective and in some cases stereospecific substitution by a free radical chain addition-elimination mechanism with 1-alkenylstannanes or -mercurials. The chain reaction is also observed for 1-alkynyl derivatives and in the photostimulated demercuration of mixed alkyl and 1-alkenyl- or 1-alkynylmercurials. Chain propagation with alkyl radical formation is also observed to occur in the reactions of β-eliminated ClHg? with Grignard reagents in PhH-THF solution. In competitive reactions of Bu3Sn? or ClHg? with pairs of alkylmercury chlorides, it is observed that a tert-butylmercurial is >1000 times more reactive than a n-butylmercurial, suggesting a concerted dissociate electron-transfer process not involving the intermediacy of RHg? species.

Reactions of Alkylmercurials with Heteroatom-Centered Acceptor Radicals

The relative reactivities of alkylmercury halides toward PhS., PhSe., or I. decrease drastically from R = tert-butyl to R = sec-alkyl to R = n-butyl, indicative that R. is formed in the rate-determining step in the attack of these radicals upon RHgCl.The alkyl radicals thus formed will enter into chain reactions in which a heteroatom-centered radical (A.) is regenerated from substrates such as RS-SR, ArSe-SeAr, ArTe-TeAr, PhSe-SO2Ar, Cl-SO2Ph; ZCH=CHA (A = Cl, I, SPh, SO2Ph); or PhCCHA (A = I, SPh, SO2Ph). β-Styrenyl (PhCH=CHA, Ph2C=CHA) and β-phenethynyl (PhCCA) systems with A = I, Br, SO2Ph also enter into chain reactions with mercury(II) salts with the ligands PhS, PhSe, PhSO2, or (EtO)2PO.The relative reactivities of a series of reagents toward t-Bu. and of PhCH=CHA, Ph2C=CHA, and PhCCA toward c-C6H11. are reported as well as the regioselectivity of t-Bu. attack observed for 1,2-disubstituted ethylenes (ZCH=CHA) with Z and A from the group Ph, Cl, Br, I, SO2Ph, SPh, Bu3Sn.Reactions of (E)- and (Z)-PhCH=CHI or MeO2CCH=CHI with t-Bu. or c-C6H11. occurred in a regioselective and stereospecific (retention) manner.Reactions of (E)- and (Z)-ClCH=CHCl occurred in a nonstereospecific manner in which the E/Z product ratio increased with the bulk of the attacking radical.A similar effect on the E/Z product ratios was observed for (Z)-MeO2CCH=CHCl.