71022-72-5

Upstream product

• 536-74-3 phenylacetylene 
• 932-88-7 1-iodo-2-phenylethyne 
• 932-87-6 1-Bromo-2-phenylacetylene 
• 70-11-1 α-bromoacetophenone 
• 71955-87-8 trichloro[(Z)-2-chloro-2-phenylethenyl]-λ⁴-tellane 

Downstream Products

• 1379470-72-0 C₂₃H₁₈ 
• 52516-81-1 (Z)-1-Chlor-1,4-diphenylbut-1-en-3-in 
• 65943-10-4 C₁₆H₁₁Cl 

Relevant academic research and scientific papers

TEMPO-Regulated Regio- and Stereoselective Cross-Dihalogenation with Dual Electrophilic X+ Reagents

A TEMPO catalyzed cross-dihalogenation reaction was established via redox-regulation of the otherwise complex system of dual electrophilic X+ reagents. Formally, the ICl, BrCl, I2 and Br2 were generated in-situ, which enabled high regio- or stereoselective access to a myriad of iodochlorination, bromochlorination and homo-dihalogenation products with a wide spectrum of functionalities. With its mild conditions and operational simplicity, this method could enable wide applications in organic synthesis, which was exemplified by divergent synthesis of two pharmaceuticals. Detailed mechanistic investigations via radical clock reaction, pinacol ring expansion and Hammett experiments were conducted, which confirmed the intermediacy of halonium ion. In addition, a dynamic catalytic model based on the versatile catalytic role of TEMPO was proposed to explain the selective outcomes.

Hydrogen-Bonding-Assisted Br?nsted Acid and Gold Catalysis: Access to Both (E)- and (Z)-1,2-Haloalkenes via Hydrochlorination of Haloalkynes

We have developed an efficient synthesis of both (Z)- and (E)-chlorohaloalkenes via hydrochlorination of haloalkynes, based on two distinct hydrogen-bond-network-assisted catalytic systems: Br?nsted acid catalysis and gold catalysis. Both systems offer high stereoselectivity, good chemical yields, and diverse functional group tolerance.

Highly stereoselective synthesis of (Z)-1,2-dihaloalkenes by a Pd-catalyzed hydrohalogenation of alkynyl halides

An unprecedented Pd-catalyzed hydrohalogenation of alkynyl halides for the regio- and stereoselective synthesis of (Z)-1,2-dihaloalkenes has been realized using [(allyl)PdCl]2 as the catalyst and cis,cis-1,5-cyclooctadiene as the ligand. The advantages of this protocol are well illustrated by the assembly of trisubstituted (Z)-enynes and multifunctional benzenes via iterative cross-coupling reactions or tandem Diels-Alder-aromatization reactions, respectively.

Regio- and Stereochemistry of Bromochlorinations of Alkynes with molecular Bromine Chloride and Dichlorobromate(1-) Ion

The bromochlorination of phenyl- and alkyl-substituted acetylenes with tetrabutylammonium dichlorobromate(1-) (1) in dichloromethane was found to be anti-stereospecific and nonregiospecific (regiospecific in the case of phenylacetylene).Whereas the addition of molecular bromine chloride (2) to phenyl-substituted acetylenes was found to give nonstereospecific and regiospecific adducts, the reaction of alkyl-substituted acetylenes gave anti-stereospecific and nonregiospecific adducts.These results suggest that the addition of 1 involves an attack of chloride ion to a three-centered ?-complex in the product-forming stage, and that the addition of 2 to phenyl-substituted acetylenes involves a vinyl cation intermediate (but a bridged bromonium ion intermediate in the case of alkyl-substituted acetylenes).

Nucleophilic attack on halogeno(phenyl)acetylenes by halide ions

Nucleophilic reactions between halogeno(phenyl)acetylenes and halide ions, ArC≡CX + Y-, where Ar = C6H5 or p-ClC 6H4, X = Cl or Br, and Y = Cl or Br, have been examined. Halogen exchange of the Finkelstein type was observed for the first time in acetylene halides in anhydrous dimethyl sulphoxide when X = Br and Y = Cl. This exchange did not occur with other X-Y combinations. In the presence of up to 20% water in dimethyl sulphoxide, or under aqueous-organic phase-transfer catalytic conditions, nucleophilic addition (formally of HY) took place for all the X-Y combinations studied. In the additions, the nucleophile Y- invariably attacked the carbon to which the phenyl group was bound. The mode of HY addition was stereospecifically trans; accordingly, the resulting dihalogenostyrenes always had the (Z)-1,2-dihalogeno-configuration.