229970-94-9Relevant articles and documents
Saturated Bioisosteres of ortho-Substituted Benzenes
Denisenko, Aleksandr,Garbuz, Pavel,Mykhailiuk, Pavel K.,Shishkina, Svetlana V.,Voloshchuk, Nataliya M.
supporting information, p. 20515 - 20521 (2020/08/21)
Saturated bioisosteres of ortho-disubstituted benzenes (bicyclo[2.1.1]hexanes) were synthesized, characterized and validated. These cores were incorporated into the bioactive compounds Valsartan, Boskalid and Fluxapyroxad instead of the benzene ring. The
An α-Cyclopropanation of Carbonyl Derivatives by Oxidative Umpolung
Bauer, Adriano,Di Mauro, Giovanni,Li, Jing,Maulide, Nuno
, p. 18208 - 18212 (2020/08/21)
The reactivity of iodine(III) reagents towards nucleophiles is often associated with umpolung and cationic mechanisms. Herein, we report a general process converting a range of ketone derivatives into α-cyclopropanated ketones by oxidative umpolung. Mechanistic investigation and careful characterization of side products revealed that the reaction follows an unexpected pathway and suggests the intermediacy of non-classical carbocations.
Fluoro-Substituted Methyllithium Chemistry: External Quenching Method Using Flow Microreactors
Colella, Marco,Degennaro, Leonardo,Higuma, Ryosuke,Ishikawa, Susumu,Luisi, Renzo,Nagaki, Aiichiro,Takahashi, Yusuke,Tota, Arianna
supporting information, p. 10924 - 10928 (2020/05/08)
The external quenching method based on flow microreactors allows the generation and use of short-lived fluoro-substituted methyllithium reagents, such as fluoromethyllithium, fluoroiodomethyllithium, and fluoroiodostannylmethyllithium. Highly chemoselective reactions have been developed, opening new opportunities in the synthesis of fluorinated molecules using fluorinated organometallics.
Palladium-Catalyzed Hydrocarbonylative Cyclization of 1,5-Dienes
Zou, Suchen,Gao, Bao,Huang, Yao,Zhang, Tianze,Huang, Hanmin
supporting information, p. 6333 - 6336 (2019/08/26)
A novel and atom-economic palladium-catalyzed isomerization-hydrocarbonylative cyclization reaction of 1,5-dienes to 2-alkylidenecyclopentanones has been developed, which provides a rapid and straightforward approach to 2-alkylidenecyclopentanones with high stereoselectivity. The reaction was found to proceed via alkene isomerization and selective hydrocarbonylative cyclization to generate 2-alkylidenecyclopentanones with high selectivity.
Iminyl Radicals by Reductive Cleavage of N-O Bond in Oxime Ether Promoted by SmI2: A Straightforward Synthesis of Five-Membered Cyclic Imines
Huang, Fei,Zhang, Songlin
supporting information, p. 7430 - 7434 (2019/10/11)
A new generation method of N-centered radicals from the reductive cleavage of the N-O bond in oxime ether promoted by SmI2 is reported for the first time. The in-situ-generated N-centered radicals underwent intramolecular cyclization to afford five-membered cyclic imines in two manners: N-centered radical addition and N-centered anion nucleophilic substitution. From a synthetic point of view, an efficient synthetic method of five-membered cyclic imines was developed. A mechanism of the transformation was proposed.
Synthesis of Difluoromethyl Ketones from Weinreb Amides, and Tandem Addition/Cyclization of o-Alkynylaryl Weinreb Amides
Phetcharawetch, Jongkonporn,Betterley, Nolan M.,Soorukram, Darunee,Pohmakotr, Manat,Reutrakul, Vichai,Kuhakarn, Chutima
supporting information, p. 6840 - 6850 (2017/12/26)
[Difluoro(phenylsulfanyl)methyl]trimethylsilane (PhSCF2SiMe3) underwent a fluoride-induced nucleophilic addition to the carbonyl group of Weinreb amides to provide the corresponding difluoro(phenylsulfanyl)methyl ketones. These were
A new strategy for accessing (S)-1-(furan-2-yl)pent-4-en-1-ol: a key precursor of Ipomoeassin family of compounds and C1–C15 domain of halichondrins
Jammula, Subba Rao,Anna, Venkateswara Rao,Tatina, Sudhakar,Krishna, Thalishetti,Sreenivas, B. Yogi,Pal, Manojit
supporting information, p. 3924 - 3928 (2016/08/09)
A highly efficient synthesis of (S)-1-(furan-2-yl)pent-4-en-1-ol, known to be an initial precursor of Ipomoeassin family of compounds and C1–C15 domain of halichondrins has been achieved via a sequence involving the use of Weinreb amide formation followed by Weinreb ketone synthesis and finally CBS (Corey–Bakshi–Shibata) reduction. Detailed study on improvement of each step is described. The title compound was converted to a potential cytotoxic agent for further pharmacological studies.
One-pot Unsymmetrical Ketone Synthesis Employing a Pyrrole-Bearing Formal Carbonyl Dication Linchpin Reagent
Heller, Stephen T.,Newton, James N.,Fu, Tingting,Sarpong, Richmond
supporting information, p. 9839 - 9843 (2015/08/19)
A one-pot procedure for the synthesis of unsymmetrical ketones utilizing a pyrrole-bearing carbonyl linchpin reagent (carbonyl linchpin N,O-dimethylhydroxylamine pyrrole; CLAmP) is reported. In contrast to other carbonyl dielectrophile equivalents, CLAmP enables the synthesis of ketones from a variety of organolithium and Grignard reagents. The electrophilic nature of CLAmP enables the addition of less reactive as well as thermally unstable nucleophiles. CLAmP was designed to form kinetically stable tetrahedral intermediates upon the addition of organometallic nucleophiles. Evidence for the existence of persistent tetrahedral intermediates was obtained through in situ IR studies.
One-Pot Direct Synthesis of Weinreb Amides from Aryl and Hetero Aryl Halides Using Co 2(CO) 8 as an Effective CO Source under Conventional Thermal Heating
Baburajan, Poongavanam,Elango, Kuppanagounder P.
, p. 541 - 548 (2015/10/29)
A successful protocol for the synthesis of Weinreb amides directly from aryl halides via aminocarbonylation with N,O-dimethyl hydroxylamine using Co2(CO)8 as an in situ CO source has been demonstrated. The effects of various reaction parameters such as temperature, base, and CO source have also been investigated and optimized. GRAPHICAL ABSTRACT.
Highly efficient and environmentally benign preparation of Weinreb amides in the biphasic system 2-MeTHF/water
Pace, Vittorio,Castoldi, Laura,Alcantara, Andres R.,Holzer, Wolfgang
, p. 10158 - 10162 (2013/09/02)
A straightforward chromatography-free preparation of Weinreb amides starting from acid halides has been achieved in the biphasic medium 2-MeTHF/water. Analytically pure compounds were isolated in excellent yields simply after removal of 2-MeTHF, which abs
