2901-28-2Relevant academic research and scientific papers
Synthesis of Allylboranes via Cu(I)-Catalyzed B-H Insertion of Vinyldiazoacetates into Phosphine-Borane Adducts
Drikermann, Denis,M??el, Robert S.,Al-Jammal, Walid K.,Vilotijevic, Ivan
supporting information, p. 1091 - 1095 (2020/02/15)
Cu(I) catalysts enable C-B bond formation via direct insertion of vinyldiazoacetates into B-H bonds of borane-phosphine Lewis adducts to form phosphine-protected allylboranes under mild conditions. The resulting allylborane-phosphine Lewis adducts can be used in the diastereoselective allylation of aldehydes directly without the need for removal of the phosphine. The allylation reaction proceeds with high diastereoselectivity and yields 5,6-disubstituted dihydropyranones after treatment with an appropriate acid.
Deoxygenative α-alkylation and α-arylation of 1,2-dicarbonyls
Arman, Hadi D.,Dang, Hang T.,Haug, Graham C.,Jin, Shengfei,Larionov, Oleg V.,Nguyen, Viet D.
, p. 9101 - 9108 (2020/09/17)
Construction of C-C bonds at the α-carbon is a challenging but synthetically indispensable approach to α-branched carbonyl motifs that are widely represented among drugs, natural products, and synthetic intermediates. Here, we describe a simple approach to generation of boron enolates in the absence of strong bases that allows for introduction of both α-alkyl and α-aryl groups in a reaction of readily accessible 1,2-dicarbonyls and organoboranes. Obviation of unselective, strongly basic and nucleophilic reagents permits carrying out the reaction in the presence of electrophiles that intercept the intermediate boron enolates, resulting in two new α-C-C bonds in a tricomponent process. This journal is
Pd(II)-catalyzed enantioselective C-H activation/C-O bond formation: Synthesis of chiral benzofuranones
Cheng, Xiu-Fen,Li, Yan,Su, Yi-Ming,Yin, Feng,Wang, Jian-Yong,Sheng, Jie,Vora, Harit U.,Wang, Xi-Sheng,Yu, Jin-Quan
supporting information, p. 1236 - 1239 (2013/03/14)
Pd(II)-catalyzed enantioselective C-H activation of phenylacetic acids followed by an intramolecular C-O bond formation afforded chiral benzofuranones. This reaction provides the first example of enantioselecctive C-H functionalizations through Pd(II)/Pd(IV) redox catalysis.
Gold-Catalyzed Electrophilic Addition to Arylalkynes. A Facile Method for the Regioselective Synthesis of Substituted Naphthalenes
Balamurugan, Rengarajan,Gudla, Vanajakshi
supporting information; experimental part, p. 3116 - 3119 (2009/12/05)
An interesting gold-catalyzed electrophilic addition to arylalkyne to synthesize substituted naphthalenes has been presented. Different metal hexafluoroantimonates have also been found to effect the transformation. Counter anion and oxo- and alkynophilicities of catalytic gold species might play an important role in this annulation reaction.
Ni-catalyzed mild arylation of α-halocarbonyl compounds with arylboronic acids
Liu, Chao,He, Chuan,Shi, Wei,Chen, Mao,Lei, Aiwen
, p. 5601 - 5604 (2008/09/17)
A simple yet powerful Ni catalyst can be used to promote direct arylations of α-halocarbonyl compounds, including a range of esters, amides, and ketones, with various arylboronic acids under mild conditions. The method tolerates β-hydrogens and functional groups in the substrates and offers reactivity and selectivity profiles that are complementary to those found in the well-established Buchwald-Hartwig approach.
REACTIVITY OF CARBANIONS. XVI. ALKYLATION OF ALKALI-METAL SALTS OF CH ACIDS WITH ELECTRON WITHDRAWING SUBSTITUENTS BY BUTYL BROMIDE
Solov'yanov, A. A.,Beletskaya, I. P.,Reutov, O. A.
, p. 1608 - 1611 (2007/10/02)
The rate constants for the reaction of the free carbanions and ion pairs were determined in the alkylation of lithium and cesium salts of phenylacetonitrile, ethyl diphenylacetate, ethyl phenylacetate, and bis(pentafluorophenyl)methane by butyl bromide in dimethoxyethane at 25 gradC.The reactivity of the carbanions increases with their conjugate CH acids in the following order: ethyl diphenylacetate (0.78 liter/mole.sec) bis(pentafluorophenyl)methane (2.7 liter/mole.sec) phenylacetonitrile (6.9 liter/mole.sec) ethyl phenylacetate (9.5 liter/mole.sec).
HIGHLY DISPERSED POTASSIUM ON ALUMINA AS A METALATING AGENT. ALKYLATION OF ENOLIZABLE COMPOUNDS
Savoia, Diego,Tagliavini, Emilio,Trombini, Claudio,Umani-Ronchi, Achille
, p. 281 - 286 (2007/10/02)
Highly dispersed potassium on alumina (K/Al2O3) acts as a metalating agent towards enolizable compounds and the intermediate organopotassium derivatives can be alkylated with primary alkyl bromides.The reaction conditions are dependent on the substrate.In particular, tetrahydrofuran is the solvent of choice for the metalation of nitriles and aldehyde N,N-dimethylhydrazones at -60 deg C and of N-cyclohexyl ketimines at room temperature, whereas hexane must be used for ketones.
