61022-41-1Relevant articles and documents
Vinyl Azides as Radical Acceptors in the Vitamin B12-Catalyzed Synthesis of Unsymmetrical Ketones
Dworakowski, Krzysztof R.,Pisarek, Sabina,Hassan, Sidra,Gryko, Dorota
, p. 9068 - 9072 (2021/11/30)
Vinyl azides are very reactive species and as such are useful building blocks, in particular, in the synthesis of N-heterocycles. They can also serve as precursors of ketones. These form in reactions of vinyl azides with nucleophiles or radicals. We have found, however, that under light irradiation vitamin B12 catalyzes the reaction of vinyl azides with electrophiles to afford unsymmetrical carbonyl compounds in decent yields. Mechanistic studies revealed that alkyl radicals are key intermediates in this transformation.
Direct Synthesis of Ketones from Methyl Esters by Nickel-Catalyzed Suzuki–Miyaura Coupling
Daneshfar, Omid,Hong, Xin,Houk, Kendall N.,Newman, Stephen G.,Xie, Pei-Pei,Zheng, Yan-Long
, p. 13476 - 13483 (2021/05/10)
The direct conversion of alkyl esters to ketones has been hindered by the sluggish reactivity of the starting materials and the susceptibility of the product towards subsequent nucleophilic attack. We have now achieved a cross-coupling approach to this transformation using nickel, a bulky N-heterocyclic carbene ligand, and alkyl organoboron coupling partners. 65 alkyl ketones bearing diverse functional groups and heterocyclic scaffolds have been synthesized with this method. Catalyst-controlled chemoselectivity is observed for C(acyl)?O bond activation of multi-functional substrates bearing other bonds prone to cleavage by Ni, including aryl ether, aryl fluoride, and N-Ph amide functional groups. Density functional theory calculations provide mechanistic support for a Ni0/NiII catalytic cycle and demonstrate how stabilizing non-covalent interactions between the bulky catalyst and substrate are critical for the reaction's success.
Intermolecular Phosphite-Mediated Radical Desulfurative Alkene Alkylation Using Thiols
Lopp, John M.,Schmidt, Valerie A.
, p. 8031 - 8036 (2019/10/19)
We report herein the development of a S atom transfer process using triethyl phosphite as the S atom acceptor that allows thiols to serve as precursors of C-centered radicals. A range of functionalized and electronically unbiased alkenes including those containing common heteroatom-based functional groups readily participate in this reductive coupling. This process is driven by the exchange of relatively weak S-H and C-S bonds of aliphatic thiols for C-H, C-C, and S-P bonds of the products formed.
Efficient, regioselective palladium-catalyzed tandem heck-lsomerization reaction of aryl bromides and non-allylic benzyl alcohols
Crawley, Matthew L.,Phipps, Kristin M.,Goljer, Lgor,Mehlmann, John F.,Lundquist, Joseph T.,Ullrich, John W.,Yang, Cuijian,Mahaney, Paige E.
supporting information; experimental part, p. 1183 - 1185 (2009/08/07)
An efficient and mild method to couple aryl bromides and activated non-allylic alcohols in a Heck reaction with tandem isomerization to selectively afford high yields of 1,5-diarylalkan-1-ones has been developed. Mechanistic insight was gained through NMR studies of products derived from deuterium-labeled intermediates.
Esters as acylating reagent in a Friedel-Crafts reaction: Indium tribromide catalyzed acylation of arenes using dimethylchlorosilane
Nishimoto, Yoshihiro,Babu, Srinivasarao Arulananda,Yasuda, Makoto,Baba, Akio
supporting information; experimental part, p. 9465 - 9468 (2009/04/06)
(Chemical Equation Presented) The Friedel-Crafts acylation of arenes with esters by dimethylchlorosilane and 10 mol % of indium tribromide has been achieved. The key intermediate RCOOSi(Cl)Me2 is generated from alkoxy esters with the evolution of the corresponding alkanes. The scope of the alkoxy ester moiety was wide: tert-butyl, benzyl, allyl, and isopropyl esters were successful. In addition, we demonstrated the direct synthesis of the indanone intermediate 11 of salviasperanol from ester 10.
In(III)-mediated chemoselective dehydrogenative interaction of ClMe 2SiH with carboxylic acids: Direct chemo- And regioselective friedel-crafts acylation of aromatic ethers
Babu, Srinivasarao Arulananda,Yasuda, Makoto,Baba, Akio
, p. 405 - 408 (2008/02/12)
Chemoselective dehydrogenative interaction of ClMe2SiH with a carboxylic acid group in the presence of InX3 is reported. 13C NMR investigation revealed the formation of PhCOOSi(Cl)Me 2as the major transient intermediate. Chemo- and regioselective Friedel-Crafts acylation of aromatic ethers directly from carboxylic acids was established.
Phenyl- and benzylphosphonate esters
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, (2008/06/13)
Compounds having the structural formula SPC1 Wherein X is an alkyl or alkenyl chain having 2-8 carbon atoms, one of which carbon atoms may be in the form of a carbonyl group, Y is H, alkyl, dialkylaminoethyl, aryl, aralkyl or aryl and aralkyl substituted
