Decarbonylative Coupling of Fluorobenzoyl Chlorides with Hexamethyldisilane in the Presence of a Palladium Complex Catalyst: Extremely Facile Decarbonylation of Pentafluorobenzoyl−Pd Complex Relevant to C₆F₅SiMe₃ Formation

Palladium−phosphite complexes catalyze the reaction of pentafluorobenzoyl chloride with hexamethyldisilane to selectively form pentafluorophenytrimethylsilane as virtually the sole product. The reaction of 3,5-difluoro- or 4-fluorobenzoyl chloride was less selective, giving a mixture of corresponding benzoyl- and phenylsilanes. Oxidative addition of pentafluorobenzoyl chloride with Pd(PPh3)4 or with Pd[P(OEt)3]2 generated in situ proceeds readily, but decarbonylation occurs, giving trans-C6F5PdClL2 (L = PPh3, P(OEt)3), selectively

Decarbonylative Coupling of Fluorobenzoyl Chlorides with Hexamethyldisilane in the Presence of a Palladium Complex Catalyst: Extremely Facile Decarbonylation of Pentafluorobenzoyl−Pd Complex Relevant to C₆F₅SiMe₃ Formation

Palladium−phosphite complexes catalyze the reaction of pentafluorobenzoyl chloride with hexamethyldisilane to selectively form pentafluorophenytrimethylsilane as virtually the sole product. The reaction of 3,5-difluoro- or 4-fluorobenzoyl chloride was less selective, giving a mixture of corresponding benzoyl- and phenylsilanes. Oxidative addition of pentafluorobenzoyl chloride with Pd(PPh3)4 or with Pd[P(OEt)3]2 generated in situ proceeds readily, but decarbonylation occurs, giving trans-C6F5PdClL2 (L = PPh3, P(OEt)3), selectively

Arylglyoxylrhodium Complexes, Their Thermolysis, and Attempted Generation by Carbonylation of an Aroylrhodium Complex

Reactions of ArCOCOCl (Ar = p-ClC6H4, Ph) with Rh(acac)(CO)2 proceeded readily to afford dimeric arylglyoxyl rhodium complexes [Rh(μ-Cl)(acac)(CO)(COCOAr)]2. [Rh(μ-Cl)(acac)(CO){COCO(p-ClC6H4)}]2 was characterized by X-ray diffraction. Thermolysis of the products showed that [Rh(μ-Cl)(acac)(CO){COCO(p-ClC6H4)}]2 was more stable than [Rh(μ-Cl)(acac)(CO)(COCOPh)]2. The reaction of p-CH3OC6H4COCOCl with Rh(acac)(CO)2 did not form a similar dimeric complex as final product, but gave p-CH3OC6H4COCl as major product, showing thermal instability of corresponding arylglyoxyl and aroyl rhodium complexes. The reaction of C6F5COCOCl did not form a simlar dimeric complex either, but a mononuclear complex RhCl(acac)(COCOC6F5)(CO)2 was generated as a transient intermediate, which was readily transformed to a furanone arising from reductive elimination of the acac ligand and C6F5COCO moiety followed by cyclization. In the thermolysis of [Rh(μ-Cl)(acac)(CO)(COCOAr)]2, only ArCOCl and Rh(acac)(CO)2 were formed, and any ArCORh species could not be detected during the thermolysis process. However, the reaction of Rh(acac)(CO)2 with PhCOCl formed RhCl(acac)(CO)2(COPh), albeit only to a small extent, suggesting that the reaction is not thermodynamically favored. The reaction of RhCl(CO)(PMe3)2 with p-ClC6H4COCOCl also proceeded cleanly to furnish p-ClC6H4COCORhCl2(CO)(PMe3)2. Thermolysis of the complex formed p-ClC6H4CORhCl2(CO)(PMe3)2, indicating slow reductive elimination of ClC6H4COCl as compared with the ArCORh species, generated in the thermolysis of [Rh(μ-Cl)(acac)(CO)(COCOAr)]2. Treatment of ClC6H4CORhCl2(CO)(PMe3)2 with carbon monoxide generates p-ClC6H4COCORhCl2(CO)(PMe3)2, although the yield was low

Synthesis of 1,2-Diketones by the Transition Metal-Catalyst-Free Reaction of α-Oxo Acid Chlorides or Oxalyl Chloride with Organostannanes

The reaction of an α-oxo acid chloride with an organostannane proceeds transition metal-catalyst-free to afford a 1,2-diketone in an excellent yield. In addition, a sequence comprising pretreatment of oxalyl chloride with an organostannane and a subsequent treatment with another organostannane also works as a convenient modification

Arylglyoxylrhodium Complexes, Their Thermolysis, and Attempted Generation by Carbonylation of an Aroylrhodium Complex

Reactions of ArCOCOCl (Ar = p-ClC6H4, Ph) with Rh(acac)(CO)2 proceeded readily to afford dimeric arylglyoxyl rhodium complexes [Rh(μ-Cl)(acac)(CO)(COCOAr)]2. [Rh(μ-Cl)(acac)(CO){COCO(p-ClC6H4)}]2 was characterized by X-ray diffraction. Thermolysis of the products showed that [Rh(μ-Cl)(acac)(CO){COCO(p-ClC6H4)}]2 was more stable than [Rh(μ-Cl)(acac)(CO)(COCOPh)]2. The reaction of p-CH3OC6H4COCOCl with Rh(acac)(CO)2 did not form a similar dimeric complex as final product, but gave p-CH3OC6H4COCl as major product, showing thermal instability of corresponding arylglyoxyl and aroyl rhodium complexes. The reaction of C6F5COCOCl did not form a simlar dimeric complex either, but a mononuclear complex RhCl(acac)(COCOC6F5)(CO)2 was generated as a transient intermediate, which was readily transformed to a furanone arising from reductive elimination of the acac ligand and C6F5COCO moiety followed by cyclization. In the thermolysis of [Rh(μ-Cl)(acac)(CO)(COCOAr)]2, only ArCOCl and Rh(acac)(CO)2 were formed, and any ArCORh species could not be detected during the thermolysis process. However, the reaction of Rh(acac)(CO)2 with PhCOCl formed RhCl(acac)(CO)2(COPh), albeit only to a small extent, suggesting that the reaction is not thermodynamically favored. The reaction of RhCl(CO)(PMe3)2 with p-ClC6H4COCOCl also proceeded cleanly to furnish p-ClC6H4COCORhCl2(CO)(PMe3)2. Thermolysis of the complex formed p-ClC6H4CORhCl2(CO)(PMe3)2, indicating slow reductive elimination of ClC6H4COCl as compared with the ArCORh species, generated in the thermolysis of [Rh(μ-Cl)(acac)(CO)(COCOAr)]2. Treatment of ClC6H4CORhCl2(CO)(PMe3)2 with carbon monoxide generates p-ClC6H4COCORhCl2(CO)(PMe3)2, although the yield was low

Palladium-Catalyzed Hydrophosphorylation of Alkynes <i>via</i> Oxidative Addition of HP(O)(OR)₂

Palladium-Catalyzed Hydrophosphorylation of Alkynes via Oxidative Addition of HP(O)(OR)2</sub

Oxidative Addition of the B−Cl Bond with Palladium Species and Insertion of Alkynes and a Vinyl Ketone into the Resulting B−Pd Bond

The chloroborane (1) reacts with Pd(η3-C3H5)(η5-C5H5) and PMe3 (2 equiv) to afford (2), which was characterized by X-ray crystallography. Treatment of complex 2 with alkynes or methyl vinyl ketone gave chloro(1-boryl-1-alken-2-yl)palladium complexes or a chloro(3-boroxy-2-buten-1-yl)palladium complex, respectively

The First Platinum(0)-Catalyzed Regio- and Stereoselective Thiosilylation of Alkynes Using Disulfides and Disilanes: A New Strategy for Introducing Two Different Heteroatoms into Carbon−Carbon Unsaturated Bonds

The First Platinum(0)-Catalyzed Regio- and Stereoselective Thiosilylation of Alkynes Using Disulfides and Disilanes:  A New Strategy for Introducing Two Different Heteroatoms into Carbon−Carbon Unsaturated Bond

Palladium- and Platinum-Catalyzed Reactions of Silacyclobutanes with Acid Chlorides Affording Cyclic Silyl Enol Ethers and/or 3-(Chlorosilyl)propyl Ketones

Palladium and platinum complexes catalyze the reaction of silacyclobutanes with acid chlorides in the presence of a large excess of a tertiary amine (triethylamine, diisopropylethylamine) at higher temperatures (∼80 °C) to give cyclic silyl enol ethers, 1-sila-2-oxa-3-cyclohexenes, in excellent yields, while the reaction in the presence of a limited quantity of the amine at room temperature forms 3-(chlorosilyl)propyl ketones in good yields

Palladium-Catalyzed Hydrophosphorylation of Alkynes <i>via</i> Oxidative Addition of HP(O)(OR)₂

Palladium-Catalyzed Hydrophosphorylation of Alkynes via Oxidative Addition of HP(O)(OR)2</sub