193361-04-5

Upstream product

• 19493-09-5 Methylenetriphenylphosphorane 
• 100-06-1 1-(4-methoxyphenyl)ethanone 
• 637-69-4 4-Methoxystyrene 
• 1228679-43-3 (E)-N′-(1-(4-methoxyphenyl)ethylidene)-4-methylbenzenesulfonohydrazide 
• 40811-01-6 1-(1-chloroethenyl)-4-methoxybenzene 
• 19361-62-7 styrene-d8 
• 768-60-5 4-methoxyphenylacetylen 
• 100-07-2 4-methoxy-benzoyl chloride 
• 35693-15-3 p-methoxyphenylmethanol-1,1-d2 

Relevant academic research and scientific papers

Palladium-Catalyzed Synthesis of Deuterated Alkenes through Deuterodechlorination of Alkenyl Chlorides

The palladium-catalyzed deuterodechlorination of alkenyl chlorides has been developed, and a variety of deuterated alkenes were synthesized with precise control of the deuterium incorporation. This catalytic process tolerates heterocyclic moieties and frameworks derived from bioactive agents. In addition to the double incorporation of deuterium, the gram-scale synthesis of a deuterated iminostilbene unit including a core substructure of carbamazepine was achieved in a high yield with an excellent degree of deuteration.

Catalytic, Directed C-C Bond Functionalization of Styrenes

A method for catalytic conversion of C(aryl)-C(alkenyl) bonds in styrene derivatives to new C-C bonds is developed. In the presence of a rhodium catalyst, the alkenyl groups of styrenes bearing a pyrazolyl directing group were efficiently converted to other carbon substituents upon reacting with various alkenes including styrenes, aliphatic alkenes, and allyl alcohols. It is also indicated that the C-C bond cleavage proceeded via a hydrometalation/β-carbon elimination pathway.

Modified shapiro reactions with bismesitylmagnesium as an efficient base reagent

Bismesitylmagnesium has been shown to successfully mediate the Shapiro reaction. A range of tosylhydrazones has been subjected to the developed system, which furnishes exceptionally high incorporation of the introduced electrophiles and good yields of the functionalized styrenes. At conveniently accessible temperatures and with a comparably small excess of base reagent, this protocol offers an efficient alternative to the lithium-mediated process. Importantly, 1.05 equiv of Weinreb amides are sufficient to obtain aryl enones in good yields.

α-Selective Ni-catalyzed hydroalumination of aryl- and alkyl-substituted terminal alkynes: Practical syntheses of internal vinyl aluminums, halides, or boronates

A method for Ni-catalyzed hydroalumination of terminal alkynes, leading to the formation of α-vinylaluminum isomers efficiently (>98% conv in 2-12 h) and with high selectivity (95% to >98% α), is described. Catalytic α-selective hydroalumination reactions proceed in the presence of a reagent (diisobutylaluminum hydride; dibal-H) and 3.0 mol % metal complex (Ni(dppp)Cl2) that are commercially available and inexpensive. Under the same conditions, but with Ni(PPh3)2Cl2, hydroalumination becomes highly β-selective, and, unlike uncatalyzed transformations with dibal-H, generates little or no alkynylaluminum byproducts. All hydrometalation reactions are reliable, operationally simple, and practical and afford an assortment of vinylaluminums that are otherwise not easily accessible. The derived α-vinyl halides and boronates can be synthesized through direct treatment with the appropriate electrophiles [e.g., Br 2 and methoxy(pinacolato)boron, respectively]. Ni-catalyzed hydroaluminations can be performed with as little as 0.1 mol % catalyst and on gram scale with equally high efficiency and selectivity.

Nickel-catalyzed regioselective hydroalkynylation of styrenes: Improved catalyst system, reaction scope, and mechanism

(Chemical Equation Presented) Addition of the sp-C H bond of triisopropylsilylacelylene to the carbon-carbon double bonds of styrenes bearing functional groups proceeded efficiently at room temperature in the presence of 3 mol % of Ni(cod)2 wit

Kinetic isotope effects in cycloreversion of rhenium (V) diolates

Cycloreversion of 4-methoxystyrene from the corresponding Tp′Re(O)(diolato) complex (Tp′ = hydrido-tris-(3,5-dimethylpyrazolyl)borate) was measured competitively for various isotopomers at 103 °C. Primary (12C/13C) and secondary (1H/2H) kinetic isotope effects were determined. The primary KIEs were k12C/k13C = 1.041 ± 0.005 at the α position and 1.013 ± 0.006 at the β position. Secondary KIEs were kH/kD = 1.076 ± 0.005 at the α position and 1.017 ± 0.005 at the β position. Computational modeling (B3LYP/LACVP*+) located a transition state for concerted cycloreversion of styrene from TpRe(O)(OCH2-CHPh) exhibiting dramatically different C-O bond lengths. A Hammett study on cycloreversions of substituted styrenes from a series of Tp′Re(O)(diolato) showed dichotomous behavior for electron donors and electron-withdrawing groups as substituents: ρ = -0.65 for electron donors, but ρ = +1.13 for electron-withdrawing groups. The data are considered in light of various mechanistic proposals. While the extrusion of 4-methoxystyrene is concluded to be a highly asynchronous concerted reaction, the Hammett study reflects a likelihood that multiple reaction mechanisms are involved.

Mechanism of the [2 + 2] photocycloaddition of fullerene C60 with styrenes

Stereochemical studies on [2 + 2] photoaddition of cis-/trans-4-propenylanisole (cis-1 and trans-1) and cis-1-(p-methoxyphenyl)ethylene-2-d1 (cis-3-d1) to C60 exhibit stereospecificity in favor of the trans-2 cycloadduct in the former case and nonstereoselectivity in the latter. The observed stereoselectivity in favor of the cis-6-d3 [2 + 2] diastereomer by 12% in the case of the photochemical addition of (E)-1-(p-methoxyphenyl)-2-methyl-prop-1-ene-3,3,3-d3 (trans-5-d3) to C60 is attributed to a steric kinetic isotope effect (k(H)/k(D) = 0.78). The loss of stereochemistry in the cyclobutane ring excludes a concerted addition and is consistent with a stepwise mechanism. Intermolecular secondary kinetic isotope effects of the [2 + 2] photocycloaddition of 3-d0 vs 3-d1, and 3-d6 as well as 5-d0 vs 5-d1, and 5-d6 to C60 were also measured. The intermolecular competition due to deuterium substitution of both vinylic hydrogens at the β-carbon of 3 exhibits a substantial inverse α-secondary isotope effect k(H)/k(D) = 0.83 (per deuterium). Substitution with deuterium at both vinylic methyl groups of 5 yields a small inverse k(H)/k(D) = 0.94. These results are consistent with the formation of an open intermediate in the rate-determining step.