15895-94-0

Upstream product

• 201230-82-2 carbon monoxide 
• 536-74-3 phenylacetylene 
• 71-36-3 butan-1-ol 
• 108-86-1 bromobenzene 
• 141-32-2 acrylic acid n-butyl ester 
• 542-69-8 1-iodo-butane 
• 93-97-0 benzoic acid anhydride 
• 100-42-5 styrene 
• 98-81-7 1-bromovinylbenzene 
• 50-00-0 formaldehyd 
• 122-43-0 butyl phenylacetate 

Relevant academic research and scientific papers

Neutral vs anionic palladium iodide-catalyzed carbonylation of terminal arylacetylenes

The hydroalkoxycarbonylation of terminal arylacetylenes can be carried out in an easy one-step synthesis through the use of PdI2 or PdI2/KI as catalytic systems under non-oxidative conditions, without other ligands and in the absence of added acids. Going from non-polar to polar reaction media, we have noticed a dramatic change in the chemoselectivity of the reaction with prevailing formation of α-, β-unsaturated esters, in the former case, and a mixture of oxidative (maleic esters derivatives) and reductive (mainly unsaturated lactones) carbonylation products in comparable amount, in the latter case. The origin of this behavior can be explained with the different active species at work changing the reaction media: neutral palladium species in non-polar media and ionic palladium species in polar media.

The role of phosphine ligands in the catalytic systems of the Heck reaction with aromatic carboxylic anhydrides

The results of a comparative study of phosphine-containing and phosphine-free catalytic systems of the Heck reaction using aromatic carboxylic anhydrides as arylating agents are presented. It was demonstrated that the patterns of diff erential selectivity of the reaction under competition of two aromatic anhydrides or two alkenes are independent of the presence of a tertiary phosphine additive in the system. It was established that palladium complexes with no phosphine ligands in their coordination sphere are catalytically active at the step of activation of aromatic carboxylic anhydride and alkene. The patterns of diff erential selectivity for regioisomers of arylated products provide the evidence of the participation of phosphine-containing anionic palladium complexes in the regioselectivity-determining step of the catalytic cycle. The data obtained are in agreement with the phosphine involvement in the catalyst transformations proceeding outside the main catalytic cycle.

Markovnikov-Selective Palladium Catalyst for Carbonylation of Alkynes with Heteroarenes

A new class of palladium catalysts, based on heterocyclic diphosphines, was rationally designed and synthesized. Application of one of these catalysts allows novel Markovnikov-selective carbonylation of non-activated alkynes with heteroarenes to give the

Stereo- and chemoselective cross-coupling between two electron-deficient acrylates: An efficient route to (Z, E)-muconate derivatives

A Ru-catalyzed direct oxidative cross-coupling reaction of acrylates was developed. It offers a straightforward and atom-economical protocol for the synthesis of functionalized (Z,E)-muconate derivatives in moderate to good yields with good stereo- and chemoselectivities. The conjugated muconates bearing differentiable terminal functionality can be selectively transformed into versatile synthetic intermediates widely used in organic synthesis.

Br?nsted acidic ionic liquid as an efficient and recyclable promoter for hydroesterification of olefins catalyzed by a triphenylphosphine-palladium complex

Several Br?nsted acidic ionic liquids (BAILs) with different acidic scales were synthesized and employed as acid promoters for the hydroesterification of olefins catalyzed by a triphenylphosphine-palladium complex. The results showed that catalysts with BAIL promoters resulted inmoderate to high conversions to the ester product with excellent selectivity, depending on the acidity of BAIL used. The reaction conversion reached a plateau when the catalyst was promoted using BAIL with a Hammett acidity function less than or equal to-0.11. This catalyst system could be reused several times for the hydroesterification of 1-hexene without a considerable decrease in the catalytic performance.

Palladium(II)-catalyzed catalytic aminocarbonylation and alkoxycarbonylation of terminal alkynes: Regioselectivity controlled by the nucleophiles

The aminocarbonylation and alkoxycarbonylation reactions of terminal alkynes took place smoothly and efficiently using a catalyst system Pd(OAc) 2-dppb-p-TsOH-CH3CN-CO under relatively mild experimental conditions. The catalytic system was tested and optimized using two different nucleophiles: alcohols and amines. Phenylacetylene (1a) was considered as an alkyne along with diisobutylamine (2b1) andmethanol (2c1) as nucleophiles. The results showed significant differences in the conversion of 1a and in the selectivity towards the gem or trans unsaturated esters or amides with these nucleophiles. The effects of the type of palladium catalysts, the type of ligands, the amount of dppb and the solvents were carefully studied. With diisobutylamine (2b1), excellent regioselectivity towards the 2-acrylamides (gem isomer, 3ab1) was almost always observed, while trans-α,β-unsaturated esters 4ac1 was the predominant product with methanol (2c1) as a nucleophile. This remarkable sensitivity in the selectivity of the reaction indicates two different possible mechanistic pathways for these carbonylation reactions. Copyright

Rationally designed pincer-type heck catalysts bearing aminophosphine substituents: PdIV intermediates and palladium nanoparticles

The aminophosphine-based pincer complexes [C6H 3-2,6-{XP(piperidinyl)2}2Pd(Cl)] (X = NH 1; X = O 2) are readily prepared from cheap starting materials by sequential addition of 1,1′,1″-phosphinetriyltripiperidine and 1,3-diaminobenzene or resorcinol to solutions of [Pd(cod)(Cl)2] (cod = cyclooctadiene) in toluene under N2 in "one pot". Compounds 1 and 2 proved to be excellent Heck catalysts and allow the quantitative coupling of several electronically deactivated and sterically hindered aryl bromides with various olefins as coupling partners at 140°C within very short reaction times and low catalyst loadings. Increased reaction temperatures also enable the efficient coupling of olefins with electronically deactivated and sterically hindered aryl chlorides in the presence of only 0.01 mol% of catalyst. The mechanistic studies performed rule out that homogeneous Pd0 complexes are the catalytically active forms of 1 and 2. On the other hand, the involvement of palladium nanoparticles in the catalytic cycle received strong experimental support. Even though pincer-type PdIV intermediates derived from 1 (and 2) are not involved in the catalytic cycle of the Heck reaction, their general existence as reactive intermediates (for example, in other reactions) cannot be excluded. On the contrary, they were shown to be thermally accessible. Compounds 1 and 2 show a smooth halide exchange with bromobenzene to yield their bromo derivatives in DMF at 100°C. Experimental observations revealed that the halide exchange most probably proceeded via pincer-type PdIV intermediates. DFT calculations support this hypothesis and indicated that aminophosphine-based pincer-type PdIV intermediates are generally to be considered as reactive intermediates in reactions with aryl halides performed at elevated temperatures.

Bridged imidazolium salts used as precursors for chelating carbene complexes of palladium in the Mizoroki-Heck reaction

A variety of chiral and achiral imidazolium salts is synthesized. Methylene-, ethylene-, propylene- and pyridinyl-bridged bis(imidazolium) halides are used to generate the respective free chelating carbenes. The synthesis of palladium complexes of general formula [cis-CH2{NC(H)=C(H)N(R)C} 2PdX2] with these chelating N-heterocyclic carbene ligands is reported. Structural proofs of complexes 28 and 46 are represented by X-ray diffraction studies. Catalytic applications in the Mizoroki-Heck reaction are presented. Georg Thieme Verlag Stuttgart.

Pd(II) - dppb and syngas catalyze regioselective hydroesterification of terminal alkynes under neutral conditions

Palladium(II) regioselectively catalyzes the hydroesterification of terminal alkynes under syngas forming α,β-unsaturated esters 3 and 4 in excellent chemical yields under neutral conditions. The high selectivity for the linear ester 4 was obtained with a catalytic system that includes Pd(II), 1,4-bis(diphenylphosphino)butane (dppb) and CO/H2 in CH2Cl2 as solvent. The control of the regioselectivity depends strongly upon the type of ligand, the solvent and the use of the syngas mixture.

Alkoxycarbonylation of phenylacetylene, catalyzed by Pd(dba)2 in the presence of an acid and a tertiary phosphine

The effect of the composition of the catalylic system Pd(dba)2/HX/(RPPh2) (dba is dibenzylideneacetone) on the yield and regioselectivity of the reaction of phenylacetylene with CO and BuOH in toluene was studied. The highest yield of butyl 2- and 3-phenylpropenoates was obtained at X = CF3COO, and the activity of the catalyst decreases with X in the order CF3COO > p-TsO > BF4 ≥ ClO4 > CF3SO3 > ClCH2COO > AcO ≈ Cl and with R in the order Ph > 2-Py > Ph2PC2H4 > Ph2P(O)C2H4 > Et.