32507-44-1

Upstream product

• 2028-85-5 (4-bromophenyl)diazonium chloride 
• 1097191-56-4 1-allyl-2-(4-bromobenzylidene)hydrazine 
• 1122-91-4 4-bromo-benzaldehyde 
• 91788-88-4 allyl-triethylphosphonium-bromide 
• 78-08-0 Triethoxyvinylsilane 
• 778641-02-4 1-bromo-4-(2-bromovinyl)benzene 
• 134619-70-8 4-bromo-4-(4-bromo-phenyl)-but-1-ene 
• 18925-10-5 allylzinc bromide 
• 49678-04-8 trans-4-bromocinnamaldehyde 
• 1779-49-3 Methyltriphenylphosphonium bromide 
• 2065-66-9 methyl-triphenylphosphonium iodide 
• 75927-49-0 pinacol vinylboronate 
• 1560-54-9 allyltriphenylphosphonium bromide 
• 82720-13-6 1-(4-bromo-phenyl)-4-chloro-but-2ξ-ene 

Downstream Products

• 54372-60-0 2-(trans-2-p-brom-phenyl-ethenyl)-1,1-dichlor-cyclopropan 
• 1394249-50-3 3-{(Z)-[(2S)-2-(4-bromophenyl)cyclohex-3-en-1-ylidene]methyl}-1,3-oxazolidin-2-one 

Relevant academic research and scientific papers

N-Methylphenothiazine S-Oxide Enabled Oxidative C(sp2)–C(sp2) Coupling of Boronic Acids with Organolithiums via Phenothiaziniums

Herein, we report the development of a transition-metal-free oxidative C(sp2)–C(sp2) coupling of readily available boronic acids and organolithiums via phenothiazinium ions. Various biaryl, styrene, and diene derivatives were obtained using this reaction system. The key to this process is N-methylphenothiazine S-oxide (PTZSO), which allows efficient conversion of boronic acids to phenothiazinium ions. The mechanism of phenothiazinium formation using PTZSO was investigated using theoretical calculations and experiments, which provided insight into the unique reactivity of PTZSO.

Stereoselective and Atom-Economic Alkenyl C-H Allylation/Alkenylation in Aqueous Media by Iridium Catalysis

A practical and atom-economic protocol for the stereoselective preparation of various 1,4-and 1,3-diene skeletons through iridium-catalyzed directed olefinic C-H allylation and alkenylation of NH-Ts acrylamides in water was developed. This reaction tolerated a wide scope of substrates under simple reaction conditions and enabled successful gram-scale preparation. Furthermore, an asymmetric variant of this reaction giving enantioenriched 1,4-dienes was achieved employing a chiral diene-iridium complex as the catalyst.

Iridium-catalyzed alkenyl C-H allylation using conjugated dienes

An iridium-catalyzed C-H allylation of acrylamides with conjugated dienes was developed, using NH-Ts amide as the directing group. The ligand- and additive-free protocol provided a convenient and atom economic synthesis of branched 1,4-diene skeletons, enabling the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3. The utility of this protocol is also demonstrated by a preparative scale, as well as C-H functionalization of artemisic amide. Furthermore, NH-Ts amide was efficiently removed by methylation and hydrolysis procedures to provide 1,4-dienoic acid.

Palladium-Catalyzed Chemoselective Protodecarboxylation of Polyenoic Acids

Conditions for the first palladium-catalyzed chemoselective protodecarboxylation of polyenoic acids to give the desired polyenes in good yields are presented. The reactions proceed under mild conditions using either a Pd(0) or Pd(II) catalyst and tolerate a variety of aryl and aliphatic substitutions. Unique aspects of the reaction include the requirement of phosphines, water, and a polyene adjacent to the carboxylic acid.

Highly-functionalized arene synthesis based on palladium on carbon-catalyzed aqueous dehydrogenation of cyclohexadienes and cyclohexenes

Transition metal-catalyzed dehydrogenation is a clean oxidation method requiring no additional oxidants. We have accomplished a heterogeneous Pd/C-catalyzed aqueous dehydrogenation of 1,4-cyclohexadienes and cyclohexenes to give the corresponding highly-functionalized arenes. Furthermore, various arenes could be efficiently constructed in a one-pot manner via a Diels-Alder reaction and the following dehydrogenation.

Organoselenium-Catalyzed Regioselective C?H Pyridination of 1,3-Dienes and Alkenes

An efficient approach for organoselenium-catalyzed regioselective C?H pyridination of 1,3-dienes to form pyridinium salts has been developed. This method was also successfully applied to direct C?H pyridination of alkenes. Fluoropyridinium reagents, or initially loaded pyridine derivatives, acted as pyridine sources in the pyridination reactions. The obtained pyridinium salts could be further converted under different conditions. This work is the first example of catalytic C-2 direct C?H functionalization of 1,3-dienes and the first case of organoselenium-catalyzed C?H pyridination.

Electrochemical selenium- and iodonium-initiated cyclisation of hydroxy-functionalised 1,4-dienes

The cobalt(I)-catalysed 1,4-hydrovinylation reaction of allyloxytrimethylsilane and allyl alcohol with substituted 1,3-dienes leads to hydroxy-functionalised 1,4-dienes in excellent regio- and diastereoselective fashion. Those 1,4-dienols can be converted

A highly selective synthesis of 1-substituted (E)-buta-1,3-dienes with 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane as building block

Highly selective synthesis of 1-substituted (E)-buta-1,3-dienes via palladium-catalyzed Suzuki-Miyaura cross-coupling of (E)-alkenyl iodides with 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane (1) is reported. The vinylboronate pinacol ester (1) acts as a vinyl building block to show high chemoselectivity for the Suzuki-Miyaura pathway versus Heck coupling in the presence of biphasic conditions (Pd(PPh3)4, aqueous K 2CO3, toluene and ethanol). Copyright

A novel ketone olefination via organozinc reagents in the presence of diphenyl phosphite

Carbonyl compounds react with organozinc reagents in the presence of diphenyl phosphite to give the corresponding olefins. A variety of 1,3-dienes and unsaturated esters were obtained in moderate to excellent yields under mild conditions. The Royal Society of Chemistry 2012.

An easy access to styrenes: Trans aryl 1,3-, 1,4- and 1,5-dienes, and 1,3,5-trienes by Hiyama cross-coupling catalyzed by palladium nanoparticles

A convenient and efficient procedure has been developed for the vinylation of aryl-, styrenyl-, cinnamyl- and dienyl-halides by a Pd(0) nanoparticle-catalyzed Hiyama cross-coupling to provide the corresponding dienes and trienes in high yields. The reaction does not require any ligand or co-catalyst, and is carried out using PdCl2 and tetrabutyl ammonium fluoride (TBAF) in THF. Pd nanoparticles are generated in situ and are the active catalytic species in this reaction. A wide range of functionalized styrenes, trans aryl 1,3-, 1,4- and 1,5- dienes, 1,2-, 1-3 and 1,4-bis(1,3-dienes), and 1,3,5-trienes can be obtained by this procedure. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2011.