38557-34-5

Upstream product

• 38704-79-9 C₆H₅CHCHCOHFe(CO)3 
• 507-19-7 t-butyl bromide 
• 917-54-4 methyllithium 
• 1720-32-7 1,6-diphenyl-hexa-1,3,5-triene 
• 17329-15-6 1,6-diphenyl-1,3,5-hexatriene 
• 104-55-2 3-phenyl-propenal 
• 169887-08-5 di-(Z)-cinnamyl sulfone 
• 169887-06-3 C₁₈H₁₈O₂S 
• 590-27-2 (E)-1,2-diiodoethene 
• 4363-35-3 Dihydroxy-styryl-boran 
• 16939-57-4 (E)-buta-1,3-dienylbenzene 
• 14371-10-9 (E)-3-phenylpropenal 
• 89530-34-7 1-phenyl-3-trimethylsilylprop-2-yn-1-ol 
• 31930-44-6 1-phenyl-3-(trimethylsilyl)prop-2-en-1-ol 

Downstream Products

• 1720-32-7 1,6-diphenyl-hexa-1,3,5-triene 
• 17329-15-6 C₁₈H₁₆ 
• 1000689-24-6 [C₆H₅(CHCH)3C₆H₅((CH₃)5C₅)RuCl] 

Relevant academic research and scientific papers

Z-selective metathesis homocoupling of 1,3-dienes by molybdenum and tungsten monoaryloxide pyrrolide (MAP) complexes

Molybdenum or tungsten monoaryloxide pyrrolide (MAP) complexes that contain OHIPT as the aryloxide (hexaisopropylterphenoxide) are effective catalysts for homocoupling of simple (E)-1,3-dienes to give (E,Z,E)-trienes in high yield and with high Z selectivities. A vinylalkylidene MAP species was shown to have the expected syn structure in an X-ray study. MAP catalysts that contain OHMT (hexamethylterphenoxide) are relatively inefficient.

Cyclopropanation of strained alkenes by palladium-catalyzed reaction of 3-trimethylsilyl- or 3-pinacolatoboryl-1-arylallyl acetates

The palladium-catalyzed cyclopropanation of strained alkenes with 3-trimethylsilyl- or 3-pinacolatoboryl-1-arylallyl acetate derivatives is described. This reaction gives cyclopropanation products in good to high yields with a single diastereomer, and the key step is likely to involve the formation of a palladacyclobutene complex from the α-trimethylsilyl- or α-pinacolatoboryl-σ-allylpalladium complex. Copyright

A highly tunable stereoselective olefination of semistabilized triphenylphosphonium ylides with N -Sulfonyl imines

The Wittig reaction involving direct olefination of triphenylphosphonium ylides (Ph3PCHR) with aldehydes is arguably the most often used method for alkene synthesis, but in general it yields mixtures of Z- and E-alkenes for semistabilized triphenylphosphonium ylides (R = aryl or vinyl). We have developed a simple and efficient protocol to improve the stereoselectivity significantly by replacing the aldehydes used in the Wittig reaction with N-sulfonyl imines, which possess distinct electronic and steric properties relative to aldehydes. A broad range of aromatic, α,β-unsaturated, and aliphatic imines bearing appropriate N-sulfonyl groups smoothly undergo olefination reaction with various benzylidenetriphenylphosphoranes or allylidenetriphenylphosphoranes under mild reaction conditions to afford an array of both Z- and E-isomers of conjugated alkenes in good to excellent yields and with greater than 99:1 stereoselectivity. Moreover, this tunable protocol has been successfully applied to the highly stereoselective synthesis of two anticancer agents, DMU-212 and its Z-isomer.

Photoisomerization of all-cis-1,6-diphenyl-1,3,5-hexatriene in the solid state and in solution: A simultaneous three-bond twist process

Disrotatory bicycle pedals: Irradiation of the title compound in the solid state gives the all-trans isomer directly in a crystal-to-crystal reaction. This threefold cis-trans photoisomerization is proposed to proceed by a two-stage mechanism that is consistent with two simultaneous bicyclepedal processes occurring in disrotatory fashion about the central bond.

A novel ambident reactivity of azolylacroleins

Reaction of azolylacroleins with phosphoranes bearing a conjugated double bond was found to yield either azolyltrienes in?a Wittig reaction, or to undergo cyclization to a dihydrobenzene containing the azole substituent. Transformation with an aza-Wittig reagent gave tetrazolylpyridines. The ambident reactivity was found to be dependent on the substituent of the phosphorane, which was rationalized by ab initio (DFT) calculation of the atomic charges of the reaction centres.

A stereoselective synthesis of 1,6-diphenyl-1,3,5-hexatrienes utilising 4,4,6-trimethyl-2-vinyl-1,3,2-dioxaborinane as a two-carbon alkenyl building block

A number of 1,6-diphenyl-1,3,5-hexatrienes of varying alkene geometries were stereoselectively prepared from just two starting materials: iodobenzene and 4,4,6-trimethyl-2-vinyl-1,3,2-dioxaborinane via a series of Heck, Suzuki-Miyaura and stereocontrolled iododeboronation reactions. These results demonstrate how 4,4,6-trimethyl-2-vinyl-1,3,2-dioxaborinane can be used as a genuine two-carbon vinyl-dianion building block in stereocontrolled polyene synthesis. The Royal Society of Chemistry 2005.

The effect of vicinyl olefinic halogens on cross-coupling reactions using Pd(0) catalysis

(trans) 1-Chloro-2-iodoethylene (3), (trans) 1-bromo-2-iodoethylene (4), (trans) 1,2-diiodoethylene (5) and (cis and trans) 1,2-dibromoethylene (11) were reacted under Suzuki, Sonogashira and Negishi cross-coupling conditions using Pd catalysis to obtain mono coupled products. Only olefin template 3 provided the desired coupling products reliably under all reaction conditions. Compound 5 did not provide cross coupled products under any of the reaction conditions used. The Negishi reaction was the only one that worked for templates 4 and 11. Studies indicate that oxidative addition of the most reactive carbon-halogen bond to Pd(0) is followed by elimination of the second halide, when the second halide is a bromide or an iodide. This happens to a much lesser degree when the second halogen is a chloride. Graphical Abstract.

Stereoselective O2-induced photoisomerization of all-trans-1,6-diphenyl-1,3,5-hexatriene

Irradiation of all-trans-1,6-diphenyl-1,3,5-hexatriene (ttt-DPH) in degassed acetonitrile (AN) gives ctt- and tct-DPH, relatively inefficiently, mainly via isomerization in the singlet excited state. The triplet contribution to the photoisomerization is small due to a very low intersystem crossing yield (φis = 0.01). Central bond isomerization is quenched in the presence of air by a factor of 1.4, consistent with the expected quenching of the lowest singlet and triplet excited states by oxygen. However, the presence of air enhances terminal bond photoisomerization by nearly twofold. Triplet-sensitized ttt-DPH photoisomerization favors tct-DPH formation and is quenched by oxygen. It follows that the interaction of singlet-excited ttt-DPH with O2 suppresses isomerization to tct-DPH but opens a new isomerization pathway to ctt-DPH. The presence of dimethylfuran, a singlet O2 trap, has no effect on the photoisomerization, eliminating the possible involvement of singlet O2 in this new reaction, ttt-DPH radical cations are ruled out as intermediates because the presence of fumaronitrile, which leads to their formation, suppresses both central and terminal bond photoisomerizations. In contrast to acetonitrile, ctt-DPH formation is quenched by oxygen in methylcyclohexane, suggesting the requirement of a polar environment. Strikingly different deuterium isotope effects distinguish the direct and O2-induced photoisomerization pathways. A comparative study of ttt-DPH-d0 with ttt-DPH-d 2 and ttt-DPH-d4, involving deuteration of one and both terminal double bonds, reveals an inverse kinetic isotope effect (k. Hox/kDox = 0.92) for the O 2-induced reaction. An attractive mechanism for the new oxygen-induced photoisomerization involves charge transfer from the S 1 state of ttt-DPH to oxygen followed by collapse of the exciplex to either a zwitterionic or a biradicaloid species through bonding at one of the benzylic positions. Rotation about the new single bond in this intermediate followed by reversion to DPH and O2 gives the observed result.

1,6-Dibromohexa-1,3,5-triene - Stereocontrolled synthesis of monosubstituted and disubstituted hexatrienes by palladium-catalysed cross-coupling reactions

1,6-Dibromohexa-1,3,5-triene, previously described by us and easily obtained from 5-bromopenta-2,4-dienal by condensation with bromomethylene triphenylphosphorane, is a versatile precursor for the synthesis of conjugated 1,3,5-trienic derivatives of contr