1,1-Diaryl derivatives acetals

In a recent article by Botella and Najera, controlled mono- and double-Heck arylations in water catalyzed by an oxime-derived palladacycle were described [22], When the reaction was carried out under microwave irradiation at 120 °C in the presence of dicyclohexylmethylamine with only 0.01 mol% of palladium catalyst (palladium acetate or palladacycle), monoarylation took place in only 10 min with a very high turnover frequency (TOF) of > 40000 (Scheme 6.3). As regards diarylation, 1 mol% of the palladacycle catalyst and 2 equivalents of iodobenzene had to be utilized to obtain moderate to good yields of diarylated product. Whereas microwave heating at 120 °C provided a 31% yield after 10 min, a 66% isolated yield of product was obtained by heating the reaction mixture under reflux for 13 h at 100 °C. Here, the... 

Highly enantioselective Mannich-type reactions of A-(2-hydroxyphenyl) aldi-mines with ketene trimethylsilyl acetals and of A-Boc-aldimines with acetyl acetone or furan are catalyzed by chiral phosphonic acids 9 derived from 3,3 -diaryl-(l )-BlNOL and POCI3 (Scheme 12.7). ... 

The lower members of the homologous series of 1. Alcohols 2. Aldehydes 3. Ketones 4. Acids 5. Esters 6. Phenols 7. Anhydrides 8. Amines 9. Nitriles 10. Polyhydroxy phenols 1. Polybasic acids and hydro-oxy acids. 2. Glycols, poly-hydric alcohols, polyhydroxy aldehydes and ketones (sugars) 3. Some amides, ammo acids, di-and polyamino compounds, amino alcohols 4. Sulphonic acids 5. Sulphinic acids 6. Salts 1. Acids 2. Phenols 3. Imides 4. Some primary and secondary nitro compounds oximes 5. Mercaptans and thiophenols 6. Sulphonic acids, sulphinic acids, sulphuric acids, and sul-phonamides 7. Some diketones and (3-keto esters 1. Primary amines 2. Secondary aliphatic and aryl-alkyl amines 3. Aliphatic and some aryl-alkyl tertiary amines 4. Hydrazines 1. Unsaturated hydrocarbons 2. Some poly-alkylated aromatic hydrocarbons 3. Alcohols 4. Aldehydes 5. Ketones 6. Esters 7. Anhydrides 8. Ethers and acetals 9. Lactones 10. Acyl halides 1. Saturated aliphatic hydrocarbons Cyclic paraffin hydrocarbons 3. Aromatic hydrocarbons 4. Halogen derivatives of 1, 2 and 3 5. Diaryl ethers 1. Nitro compounds (tertiary) 2. Amides and derivatives of aldehydes and ketones 3. Nitriles 4. Negatively substituted amines 5. Nitroso, azo, hy-drazo, and other intermediate reduction products of nitro com-pounds 6. Sulphones, sul-phonamides of secondary amines, sulphides, sulphates and other Sulphur compounds... 

Pyrrole- and indole-carboxylic acid chlorides react with dialkyl- and diaryl-cadmium to yield the ketones and it is noteworthy that the reaction of the anhydride of indole-2,3-dicarboxylic acid with diphenylcadmium produces 3-benzoylindole-2-carboxylic acid and not its isomer (53JCS1889). The ability of l-methylindole-2-carboxylic acid to react with nucleophiles is enhanced by conversion into the mixed anhydride with methanesulfonic acid. The mixed anhydride reacts with carbanions derived from diethyl malonate and from methyl acetate to yield the indolyl (3- keto esters (80TL1957). 

Using similar chemistry l,3-diaryl-2-thiobarbituric acid is acylated with chloroacetyl chloride in the presence of triethylamine. Subsequent (9-alkylation under the mildly basic conditions of sodium acetate yields the 5-oxo derivative <91H(32)907>. It is not necessary to use barbituric acid derivatives to accomplish synthesis of furopyrimidines. Other 6-oxopyrimidines serve well in developing analogues. For example, in a reaction similar to that described above, the acylated pyrimidine (215) undergoes cyclization to a 4-(substituted)amino compound (216) (Equation (74)) <92MI 707-03). 

Diaryl ditellurium compounds, when heated in pyridine, ethanol, or acetic acid with selenium dioxide, produced the corresponding bis[aryltelluro] selenium and derivatives of these compounds with oxygen bonded to tellurium and selenium4. 

Diaryl ditellurium compounds catalyzed the oxidation of aryl-substituted olefins by /-butyl hydroperoxide, hydrogen peroxide, 3-chloroperbenzoic acid, pure oxygen, or air in the presence of sulfuric acid. When the reactions were carried out in refluxing methanol, the vic-dimethoxy compounds were obtained. With acetic acid as the reaction medium, the vic-diacetoxy derivatives were isolated, text.-Butyl hydroperoxide was the best oxidizing agent with yields approaching 100%. ... 

Acetic, succinic and malonic acids (Table 1) are reported (4) to derive from Ar-CHa, Ar(CH2)2Ar (including hydroaromatic) and Ar-CH2 Ar (Ar - aromatic ring) units respectively. Examination of the concentrations of these major aliphatic products suggests that the medium lithotypes contain the highest concentrations of aryl methyl and Ar(CH2)2Ar structures. Diaryl methane units are proposed to be most significant in the pale lithotype possibly reflecting a resin input. 

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