4714-14-1Relevant academic research and scientific papers
Ruthenium-Catalyzed Reductive Arylation of N-(2-Pyridinyl)amides with Isopropanol and Arylboronate Esters
Ronson, Thomas O.,Renders, Evelien,Van Steijvoort, Ben F.,Wang, Xubin,Wybon, Clarence C. D.,Prokopcová, Hana,Meerpoel, Lieven,Maes, Bert U. W.
, p. 482 - 487 (2019/01/04)
A new three-component reductive arylation of amides with stable reactants (iPrOH and arylboronate esters), making use of a 2-pyridinyl (Py) directing group, is described. The N-Py-amide substrates are readily prepared from carboxylic acids and PyNH2, and the resulting N-Py-1-arylalkanamine reaction products are easily transformed into the corresponding chlorides by substitution of the HN-Py group with HCl. The 1-aryl-1-chloroalkane products allow substitution and cross-coupling reactions. Therefore, a general protocol for the transformation of carboxylic acids into a variety of functionalities is obtained. The Py-NH2 by-product can be recycled.
Kinetics of α-(2,6-Dimethylphenl)vinyllithium: How to Control Errors Caused by Inefficient Mixing with Pairs of Rapidly Competing Ketones
Knorr, Rudolf,Knittl, Monika,Behringer, Claudia,Ruhdorfer, Jakob,B?hrer, Petra
, p. 2843 - 2854 (2017/03/23)
Kinetic studies are a suitable tool to disclose the role of tiny reagent fractions. The title compound 2 reacted in a kinetic reaction order of 0.5 (square root of its concentration) with an excess of the electrophiles ClSiMe3, 1-bromobutane (n-BuBr), or 1-iodobutane (n-BuI) at 32 °C in Et2O or in hydrocarbon solvents. This revealed that the tiny (NMR-invisible) amount of a deaggregated equilibrium component (presumably monomeric 2) was the reactive species, whereas the disolvated dimer 2 was only indirectly involved as a supply depot. Selectivity data (relative rate constants κobs) were collected from competition experiments with the faster reactions of 2 in THF and the addition reactions of 2 to carbonyl compounds. This provided the rate sequences of Et2C=O > dicyclopropyl ketone > t-Bu-C(=O)-Ph > diisopropyl ketone ? t-Bu2C=O > ClSiMe3 > n-BuI > n-BuBr ≈ (bromomethyl)cyclopropane (but t-Bu2C=O 3 in THF only) and also of cyclopropanecarbaldehyde > acetone ≥ t-Bu-CH=O. It is suggested that a deceivingly depressed selectivity (1 obs A/kB), caused by inefficient microscopic mixing of a reagent X with two competing substrates A and B, may become evident toward zero deviation from the correlation line of the usual inverse (1/T) linear temperature dependence of ln κobs.
Hydrogenated acridine derivative and its application
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Paragraph 0133; 0134; 0135; 0137, (2016/10/08)
The invention relates to the field of chemical synthesis, and particularly relates to a compound with the general formula being Y-L-X and an application of the compound serving as a calcium channel blocking agent or/and an acetylcholinesterase inhibitor. The compound with the general formula being Y-L-X can be used for adjusting calcium homeostasis and treating cardiovascular diseases, stroke or dementia.
Luminescent Ce(III) Complexes as Stoichiometric and Catalytic Photoreductants for Halogen Atom Abstraction Reactions
Yin, Haolin,Carroll, Patrick J.,Anna, Jessica M.,Schelter, Eric J.
supporting information, p. 9234 - 9237 (2015/08/11)
Luminescent Ce(III) complexes, Ce[N(SiMe3)2]3 (1) and [(Me3Si)2NC(RN)2]Ce[N(SiMe3)2]2 (R = iPr, 1-iPr; R = Cy, 1-Cy), with C3v and C2v solution symmetries display absorptive 4f → 5d electronic transitions in the visible region. Emission bands are observed at 553, 518, and 523 nm for 1, 1-iPr, and 1-Cy with lifetimes of 24, 67, and 61 ns, respectively. Time-dependent density functional theory (TD-DFT) studies on 1 and 1-iPr revealed the 2A1 excited states corresponded to singly occupied 5dz2 orbitals. The strongly reducing metalloradical character of 1, 1-iPr, and 1-Cy in their 2A1 excited states afforded photochemical halogen atom abstraction reactions from sp3 and sp2 C-X (X = Cl, Br, I) bonds for the first time with a lanthanide cation. The dehalogenation reactions could be turned over with catalytic amounts of photosensitizers by coupling salt metathesis and reduction to the photopromoted atom abstraction reactions.
Nickel-catalyzed asymmetric reductive cross-coupling between vinyl and benzyl electrophiles
Cherney, Alan H.,Reisman, Sarah E.
supporting information, p. 14365 - 14368 (2014/12/11)
A Ni-catalyzed asymmetric reductive cross-coupling between vinyl bromides and benzyl chlorides has been developed. This method provides direct access to enantioenriched products bearing aryl-substituted tertiary allylic stereogenic centers from simple, stable starting materials. A broad substrate scope is achieved under mild reaction conditions that preclude the pregeneration of organometallic reagents and the regioselectivity issues commonly associated with asymmetric allylic arylation.
Catalytic asymmetric reductive acyl cross-coupling: Synthesis of enantioenriched acyclic α,α-disubstituted ketones
Cherney, Alan H.,Kadunce, Nathaniel T.,Reisman, Sarah E.
supporting information, p. 7442 - 7445 (2013/06/27)
The first enantioselective Ni-catalyzed reductive acyl cross-coupling has been developed. Treatment of acid chlorides and racemic secondary benzyl chlorides with a NiII/bis(oxazoline) catalyst in the presence of Mn0 as a stoichiometric reductant generates acyclic α,α-disubstituted ketones in good yields and high enantioselectivity without requiring stoichiometric chiral auxiliaries or pregeneration of organometallic reagents. The mild, base-free reaction conditions are tolerant of a variety of functional groups on both coupling partners.
Two-fold modification of the phenyl substituent in phenylphosphonic acid monoester monoamides
Stankevic, Marek,Bazan, Jolanta
, p. 8244 - 8256 (2013/01/15)
Phenylphosphonic acid ethyl ester N,N-diethylamide was subjected to a double modification of its phenyl substituent through directed ortho-metalation followed by dearomatization of the aryl substituent under Birch reduction conditions. Application of the same methodology to a diastereomerically pure phenylphosphonic acid monoester monoamide led to the formation of P-stereogenic cyclohexadienyl-phosphonic acid derivatives. The method offers a simple and efficient modification of phenyl substituent in organophosphorus compounds.
The leaving group dependence in the rates of solvolysis of 1,2-diphenylethyl system
Santhosh Kumara,Jayakumarb,Balachandranc
experimental part, p. 783 - 788 (2011/05/05)
1,2-Diphenylethyl chloride undergoes solvolysis by SN1 mechanism in aqueous organic solvents. The α-phenyl group of 1,2-diphenylethyl chloride enters into conjugation with the developing carbocationic centre. The β-phenyl group on the other hand was unable to extend its conjugation via neighbouring group participation due to steric inhibition of resonance in the formation of non-classical carbocation. 1,2-Diphenylethyl chloride thus behaves similar to 1-phenylethyl chloride in its solvolysis pattern. The solvolytic rate studies of chloride and methanesulphonate of 1,2-diphenylethyl alcohol in various aqueous organic solvents show that the dispersion observed in the Winstein- Grunwald plot is not due to a change in leaving group but due to the difference in solvation requirements of aromatic and aliphatic groups. Copyright
Palladium-catalyzed oxidative arylhalogenation of alkenes: Synthetic scope and mechanistic insights
Kalyani, Dipannita,Satterfield, Andrew D.,Sanford, Melanie S.
supporting information; experimental part, p. 8419 - 8427 (2010/08/04)
This article describes the development of a Pd-catalyzed reaction for the arylhalogenation (halogen = Cl or Br) of diverse α-olefins by oxidatively intercepting Mizoroki-Heck intermediates. These transformations afford synthetically useful 1,2- and 1,1-arylhalogenated products in good yields with good to excellent selectivities that can be modulated by changing the nature of the halogenating reagent and/or the reaction conditions. The selectivity of these reactions can be rationally tuned by (i) controlling the relative rates of oxidative functionalization versus β-hydride elimination from equilibrating PdII-alkyl species and (ii) stabilization of organometallic PdII intermediates through the formation of π-benzyl adducts. These arylhalogenations exhibit modest to excellent levels of stereoselectivity, and the key carbon-halogen bond-forming step proceeds with predominant retention of stereochemistry at carbon.
Probing the formation of bicyclo[4.2.0]octan-1-ols
Loughlin, Wendy A.,Rowen, Catherine C.,Healy, Peter C.
, p. 5690 - 5698 (2007/10/03)
Reaction of lithium enolates of simple ketones with (±)-phenyl vinyl sulfoxide has potential for the convergent construction of complex fused ring systems containing a bicyclo[n.2.0]alkan-1-ol. The formation of sulfinylbicyclo[4.2.0]octan-1-ols 1-3 from the lithium enolate of cyclohexanone with (±)-phenyl vinyl sulfoxide or (R)-(+)-p-tolyl vinyl sulfoxide 18 was used to probe the mode of this novel cyclization reaction. Using phenyl vinyl sulfoxide, variations in the reaction lighting and solvent were investigated, in conjunction with radical trapping (TEMPO) and isotope labeling (deuterium) experiments. Cyclization to form sulfinylbicyclooctanols 1-3 is likely to proceed via an intermediate that ring closes to the bicycloalkanol anion 11 and was presently favored by the use of solvents such as THF or DME.
