83026-52-2Relevant academic research and scientific papers
Carbon–carbon bond formation via benzoyl umpolung attained by photoinduced electron-transfer with benzimidazolines
Igarashi, Tomohito,Tayama, Eiji,Iwamoto, Hajime,Hasegawa, Eietsu
supporting information, p. 6874 - 6877 (2019/04/10)
A photoreaction between benzoyl compounds, such as benzoylformate derivatives, and 2-(p-anisyl)-1,3-dimethylbenzimidazoline in the presence of allyl bromide was found to give various allylated alcohols. In the reaction of benzoylformates, α-hydroxy ester enolates, for which the negative charge occurs on the carbonyl carbon of benzoyl (umpolung reactivity), are proposed to be generated as intermediates by electron-transfer from benzimidazolines to the photoexcited benzoylformates; these species react with allyl bromide to produce α-allyl-α-hydroxy esters.
Photo-allylation and photo-benzylation of carbonyl compounds using organotrifluoroborate reagents
Nishigaichi, Yutaka,Orimi, Takayuki,Takuwa, Akio
experimental part, p. 3837 - 3839 (2010/03/04)
Allyl- and benzyl-trifluoroborates can be applied to the photoreaction of carbonyl compounds to afford the corresponding alcoholic adducts in acceptable yields via a photo-induced single electron transfer pathway. The results were confirmed from the react
Stereoselective synthesis of Z-α-aryl-α,β-unsaturated esters
Mani, Neelakandha S.,Mapes, Christopher M.,Wu, Jiejun,Deng, Xiaohu,Jones, Todd K.
, p. 5039 - 5042 (2007/10/03)
An efficient method for the stereoselective synthesis of (Z)-α-arylacrylates is described. Treatment of α-hydroxyesters with triflic anhydride and pyridine at 0 °C followed by warming to room temperature afforded the corresponding (Z)-α-aryl-α,β- unsatura
Nucleophilic benzoylation using lithiated methyl mandelate as a synthetic equivalent of the benzoyl carbanion. Oxidative decarboxylation of α-hydroxyacids
Blay, Gonzalo,Fernández, Isabel,Formentin, Pilar,Monje, Belén,Pedro, José R,Ruiz, Rafael
, p. 1075 - 1081 (2007/10/03)
The synthesis of alkyl aryl ketones using lithiated methyl mandelate as a synthetic equivalent of the benzoyl carbanion is reported (Umpolung). The methodology involves alkylation of methyl mandelate, hydrolysis of the ester group and oxidative decarboxylation of the resulting α-hydroxyacids. The last step is carried out in a catalytic aerobic way using a Co(III) complex in the presence of pivalaldehyde under very mild and advantageous conditions. The procedure is also applied to methyl mandelates substituted on the aromatic ring.
Catalytic aerobic oxidative decarboxylation of α-hydroxy-acids. Methyl mandelate as a benzoyl anion equivalent
Blay, Gonzalo,Fernandez, Isabel,Formentin, Pilar,Pedro, Jose R.,Rosello, Antonio L.,Ruiz, Rafael,Journaux, Yves
, p. 3327 - 3330 (2007/10/03)
The monomeric square-planar cobalt(III) complex of bis-N,N'- disubstituted oxamides catalyses the oxidative decarboxylation of α-hydroxy acids with molecular oxygen/pivalaldehyde with very good yields. This reaction offers an interesting alternative in the use of methyl mandelate as a convenient benzoyl anion equivalent.
Ester Enolates from α-Acetoxy Esters. Synthesis of Aryl Malonic and α-Aryl Alkanoic Esters from Aryl Nucleophiles and α-Keto Esters
Ghosh, Subrata,Pardo, Simon N.,Salomon, Robert G.
, p. 4692 - 4702 (2007/10/02)
Ester enolates are generated by reductive α-deacetoxylation of α-acetoxy-α-arylmalonic esters or α-acetoxy-α-arylalkanoic esters with lithium in liquid ammonia or sodium α-(dimethylamino)naphthalenide in hexamethylphosphoramide-benzene.Since the requisite α-acetoxy esters are available from aryl nucleophiles, the reductions provide effective new synthetic routes to arylmalonic esters and α-arylalkanoic esters.For example, 2-(p-isobutylphenyl)propionic acid (ibuprofen, a commercially important nonsteroidal antiinflammatory agent) is obtained in 73percent yield overall from isobutylbenzene.Arenes, aryllithiums, or arylmagnesium halides react with α-keto esters, e.g., diethyl oxomalonate, ethyl pyruvate, methyl phenylglyoxalate, or alkyl glyoxylates, to afford α-hydroxy esters.These are acetylated with acetic anhydride-triethylamine and p-(dimethylamino)pyridine as a catalyst.Reductive α-deoxygenation then allows replacement of the acetoxy group by hydrogen or an alkyl group.
