Catalytic Amount Of PdCl2 Research Articles

Synthesis and Application of a Novel Modified Polysiloxane Polymer with High Reaction Activity as Water Repellent Agent for Cotton Fabrics

A novel poly(4-iodobutoxylmethylsiloxane) (PIBMS) water repellent with high reaction activity was synthesized using poly(hydromethylsiloxane) (PHMS), methyl iodide (MeI) and tetrahydrofuran (THF) in the presence of a catalytic amount of PdCl2. The new chemical active group of PIBMS could covalently bond to the cotton fabric. It is conducive to improve the washability of treated cotton fabric. The structure of PIBMS was confirmed by the FT-IR and 1H NMR spectra. The PIBMS was applied onto cotton fabric by a pad-dry-cure process. PIBMS was applied to cotton fabrics and the effect of the process parameters on water repellent performance was studied. The morphology of PIBMS polymer film on the cotton fabric was investigated by SEM. The water repellency of treated cotton fabrics before and after vigorous washes was compared. The results show that the water repellent grade of cotton fabric treated with PIBMS was 90. The contact angle of the treated cotton fabric was 136.94°, which was higher than that of the untreated cotton fabric. The water repellent grade of treated cotton fabric was still as high as 80 after 20 times washing. The tear strength and the tensile strength of cotton fabric significantly increased after PIBMS treatment. The air permeability and the water vapor permeability of treated cotton fabric were slightly lower than those of untreated cotton fabrics.

Synthesis of a Polysiloxane with High Reaction Activity

A novel building block in organic synthesis, poly (4-iodobutoxylmethylsiloxane)(PIBMS) with high reaction activity was prepared by poly (hydromethylsiloxane)(PHMS), methyl iodide and tetrahydrofuran (THF) in the presence of a catalytic amount of PdCl2. The structure of PIBMS was characterized by the FT-IR and NMR spectra. The reaction conditions were optimized.

Simultaneous dehalogenation and hydrogenation reduction of halogen-heteroaromatic aldehydes

Treatment of halogen-heteroaromatic aldehydes with catalytic amount of PdCl2 under atmosphere pressure of hydrogen in base medium (sodium acetate) leads to the corresponding dehalogenated primary alcohols. The reaction system was especially effective for the heteroaromatic compounds bearing aldehyde groups and halides (bromo- or chloro-functions).

Microwave-assisted efficient synthesis of 2-arylbenzo[b]furans and 2-ferrocenylbenzo[b]furans from readily prepared propargylic alcohols and o-iodophenols

A simple, efficient and expeditious method for synthesis of 2-arylbenzo[b]furans and 2-ferrocenylbenzo[b]furans from readily prepared propargylic alcohols, o-iodophenols and silica gel with the catalyst of PdCl2(PPh3)2 (2 mol%)/CuI (2 mol%) and microwave-promoted Sonogashira coupling/cyclization reaction is developed. The methodology can produce good to excellent yields. In addition, this method can also be completed in one-pot with iodobenzene, 2-methyl-3-butyn-2-ol and 2-iodo-4-methylphenol as reactants. A simple and efficient method for synthesis of 2-arylbenzo[b]furnas and 2-ferrocenylbenzo[b]furans has been developed from the Sonogashira coupling/cyclization reaction of propargylic alcohols and o-iodophenols in the presence of silica gel and catalytic amounts of PdCl2(PPh3)2 (2 mol%) and CuI (2 mol%) under microwave conditions.

On the PdCl2-catalyzed synthesis of allylic azides and allylic sulfonamides from homoallylic alcohols

According to experimental and literature data, the one-pot formation of allylic azides or sulfonamides from catalytic amounts of PdCl2, homoallylic alcohols and TMSN3 or TsNH2 occurs through CC migration followed by regioselective nucleophilic addition on the PdII-activated CC bond and β-OH elimination.

A simple and efficient protocol for a palladium-catalyzed ligand-free Suzuki reaction at room temperature in aqueous DMF

A convenient, effective and mild protocol has been developed for the palladium-catalyzed ligand-free Suzuki reaction of aryl bromides with arylboronic acids in aqueous N,N-dimethylformamide (DMF) in the presence of K2CO3 and a catalytic amount of PdCl2 in air at room temperature. It is noteworthy that the volume ratio of water–DMF and base play important roles in the reaction, and various functional groups are tolerated under the optimized conditions. Furthermore, this protocol could be extended to the cross-couplings of nitrogen-based heteroaryl halides with arylboronic acids in moderate to excellent yields.

ChemInform Abstract: 3-Aryl-3-butenoic Acids and Their Esters: Practical Synthesis from Diketene by the Palladium-Catalyzed Grignard Coupling Reaction and Application as Monomers for the Radical Copolymerization with Styrene.

Treatment of arylmagnesium bromide with an equimolar amount of zinc chloride followed by the reaction with diketene in the presence of a catalytic amount of PdCl2(PPh3)2 provided an improved synthetic method for 3-aryl-3-butenoic acids in a large scale. Application as a monomer for the substituted polystyrenes is exemplified by the copolymerization of methyl 3-phenyl-3-butenoate with styrene.

Oxidation of alkynes using PdCl2/CuCl2 in PEG as a recyclable catalytic system: one-pot synthesis of quinoxalines

Alkynes were oxidized efficiently using the catalytic amount of PdCl2 and CuCl2 in PEG-400 in the presence of water, providing excellent yields of the corresponding 1,2-diketones. A variety of alkynes were well-suited substrates for the oxidation under the described conditions. Further, the optimized conditions were successfully utilized for the one-pot synthesis of 2,3-disubstituted quinoxaline derivatives.

Highly Regioselective Intermolecular Arylation of 1,2,3,4-Tetrahydropyridines

Using a catalytic amount of PdCl2(dppf) x CH2Cl2 in combination with Ag3PO4 and NaOAc, a range of arylated 1,2,3,4-tetrahydropyridines are synthesized in good yields and with complete selectivity at the beta-position. The reaction is compatible with a variety of electron-donating and electron-withdrawing aryl iodides as well as with heteroaryl iodides. The application of these tetrahydropyridines toward the synthesis of polysubstituted piperidines is also demonstrated.

Palladium‐Catalyzed Three‐Component Tethering: Synthesis of 1‐Alkoxy‐1H‐furo[3,4‐c]pyridine‐3‐ones.

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An atom-efficient palladium-catalyzed cross-coupling reaction of triarylbismuths with acid chlorides: synthesis of diaryl and alkyl aryl ketones

The cross-coupling reaction of triarylbismuths with acid chlorides using a catalytic amount of PdCl 2/PPh 3 afforded the corresponding ketones in high yields. The reactions of aromatic and aliphatic acid chlorides occurred with atom efficiency, as 3 equiv of acid chlorides coupled effectively with 1 equiv of triarylbismuths to yield 3 equiv of the corresponding diaryl and alkyl aryl ketones.

Development, Scope, and Mechanism of the Palladium-Catalyzed Intramolecular Hydroalkylation of 3-Butenyl β-Diketones.

Reaction of 7-octene-2,4-dione (3) with a catalytic amount of PdCl2(CH3CN)2 (4) (10 mol %) in dioxane at room temperature for 16 h formed 2-acetylcyclohexanone (5) in 81% yield as a single regioisomer. Byproducts in the conversion of 3 to 5 include 2,4-octanedione (13), 2-acetyl-2-cyclohexenone (14), 2-acetylphenol (15), (E)- and (Z)-6-octene-2,4-dione (17), (E)- and (Z)-5-octene-2,4-dione (18), the η3-β-diketonate chloride dimer {[η3-CH3CH2CH2CHCOHCHAc]Pd(Cl)}2 (12), and the π(allyl)palladium chloride dimer {[η3-CH3CHCHCHC(O)CH2Ac]Pd(Cl)}2 (16). The palladium-catalyzed cyclization of 3-butenyl β-diketones tolerated substitution at the terminal acyl carbon atom, the enolic carbon atom, and the terminal olefinic carbon atom. Deuterium-labeling studies, in conjunction with kinetic and in situ NMR experiments, supported a mechanism for the palladium-catalyzed hydroalkylation of 3-butenyl β-diketones initiated by 6-endo-trig attack of the enol carbon atom on a palladium-complexed olefin to form a palladium cy...

Palladium(II)-catalyzed ring expansion of a 1-alkenyl cyclopentanol

7,7-Dimethyl-2-methylenenorbornan-1-ol, a strained bicyclic 1-alkenyl cyclopentanol, undergoes Wagner–Meerwein rearrangement to fenchone under treatment with a catalytic amount of PdCl 2(PPh 3) 2 in refluxing N-methylpyrrolidin-2-one. The described reaction constitutes the first example of the palladium(II)-catalyzed ring expansion of 1-alkenyl cyclopentanols to the corresponding cyclohexanones.

Development, Scope, and Mechanism of the Palladium-Catalyzed Intramolecular Hydroalkylation of 3-Butenyl β-Diketones

Reaction of 7-octene-2,4-dione (3) with a catalytic amount of PdCl2(CH3CN)2 (4) (10 mol %) in dioxane at room temperature for 16 h formed 2-acetylcyclohexanone (5) in 81% yield as a single regioisomer. Byproducts in the conversion of 3 to 5 include 2,4-octanedione (13), 2-acetyl-2-cyclohexenone (14), 2-acetylphenol (15), (E)- and (Z)-6-octene-2,4-dione (17), (E)- and (Z)-5-octene-2,4-dione (18), the η3-β-diketonate chloride dimer {[η3-CH3CH2CH2CHCOHCHAc]Pd(Cl)}2 (12), and the π(allyl)palladium chloride dimer {[η3-CH3CHCHCHC(O)CH2Ac]Pd(Cl)}2 (16). The palladium-catalyzed cyclization of 3-butenyl β-diketones tolerated substitution at the terminal acyl carbon atom, the enolic carbon atom, and the terminal olefinic carbon atom. Deuterium-labeling studies, in conjunction with kinetic and in situ NMR experiments, supported a mechanism for the palladium-catalyzed hydroalkylation of 3-butenyl β-diketones initiated by 6-endo-trig attack of the enol carbon atom on a palladium-complexed olefin to form a palladium cy...

Palladium‐Catalyzed Cyclization/Carboalkoxylation of Alkenyl Indoles.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Palladium-catalyzed cyclization/carboalkoxylation of alkenyl indoles.

Reaction of 1-methyl-2-(4-pentenyl)indole with a catalytic amount of PdCl2(CH3CN)2 (5 mol %) and a stoichiometric amount of CuCl2 (3 equiv) in methanol under CO (1 atm) at room temperature for 30 min led to cyclization/carboalkoxylation to form the corresponding tetrahydrocarbazole in 83% isolated yield as a single regioisomer. Palladium-catalyzed cyclization/carboalkoxylation of 2-(4-pentenyl)indoles tolerated substitution along the alkenyl chain and at the internal and cis-terminal olefinic positions. Palladium-catalyzed cyclization/carboalkoxylation tolerated a range of alcohols and was effective for the cyclization of 2-(3-butenyl)indoles, 3-(3-butenyl)indoles, 3-(4-pentenyl)indoles, and 2-(5-hexenyl)indoles.

Palladium‐Catalyzed Oxidative Alkoxylation of α‐Alkenyl β‐Diketones to Form Functionalized Furans.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Palladium-catalyzed isomerization of (homo-)allylic alcohols in molten tetrabutylammonium bromide, a recyclable system

Saturated ketones have been produced by heating secondary allylic alcohols and catalytic amounts of PdCl2 or Pd(OAc)2 in molten n-Bu4NBr. After extraction of the organic material with diethyl ether, the ionic layer and the catalyst can be reused directly. Linear secondary homoallylic alcohols led also to the corresponding saturated ketones as main products. The procedure was less selective for primary allylic alcohols.

Palladium-catalyzed oxidative alkoxylation of alpha-alkenyl beta-diketones to form functionalized furans.

Treatment of 4-allyl-2,6-dimethyl-3,5-heptanedione with a catalytic amount of PdCl(2)(CH(3)CN)(2) (5 mol %) and a stoichiometric amount of CuCl(2) (2.2 equiv) in dioxane at 60 degrees C for 12 h formed 3-isobutyryl-2-isopropyl-5-methylfuran in 77% isolated yield. A number of alpha-alkenyl beta-diketones underwent oxidative alkoxylation under these conditions to form 2,3,5-trisubsituted furans in moderate to good yield.

Palladium-catalyzed alkylation of unactivated olefins

Abstract The reaction of a 3-butenyl β-diketone with a catalytic amount of PdCl2(CH3CN)2 in dioxane at room temperature led to olefin hydroalkylation and formation of the corresponding 2-acylcyclohexanone in good yield as a single regioisomer. Deuterium-labeling experiments for the hydroalkylation of 7-octene-2,4-dione were in accord with a mechanism involving outer-sphere attack of the pendant enol on a palladium-complexed olefin to form a palladium cyclohexyl species, followed by palladium migration via iterative β-hydride elimination/addition and protonolysis from a palladium enolate complex. In comparison to a 3-butenyl β-diketone, reaction of a 4-pentenyl β-diketone with a catalytic amount of PdCl2(CH3CN)2 in the presence of CuCl2 led to oxidative alkylation and formation of the corresponding 2-acyl-3-methyl-2-cyclohexenone in good yield as a single isomer. Unactivated olefins tethered to less reactive carbon nucleophiles such as β-keto esters, α-aryl ketones, and even dialkyl ketones underwent palladium-catalyzed hydroalkylation in the presence of Me3SiCl or HCl to form the corresponding cyclohexanones in moderate-to-good yield with high regioselectivity.