695-98-7Relevant articles and documents
Use of α,ω-Dichloroketimine Building Blocks for the Construction of 1-Azabicyclo[31.0]hexanes, Piperidines, Pyridines, Pyrroles, and Tetrahydroindoles
Piens, Nicola,Aelterman, Wim,D'Hooghe, Matthias,De Kimpe, Norbert
, p. 207 - 213 (2017/01/25)
A variety of different N-[2-chloro-4-(chloromethyl)pent-4-enylidene]amines and N-(2,6-dichlorohex-4-enylidene)amines was prepared for the first time, and their reactivity as eligible building blocks for the synthesis of biologically relevant nitrogen-containing heterocyclic compounds was studied. In this way, a convenient entry into functionalized 1-azabicyclo[3.1.0]hexanes, piperidines, pyridines, pyrroles, and tetrahydroindoles was developed, pointing to the broad synthetic flexibility of these dichlorinated imine substrates.
Ruthenium-catalyzed oxidative coupling of primary amines with internal alkynes through C-H bond activation: Scope and mechanistic studies
Ruiz, Sara,Villuendas, Pedro,Ortu?o, Manuel A.,Lled?s, Agustí,Urriolabeitia, Esteban P.
supporting information, p. 8626 - 8636 (2015/06/02)
The oxidative coupling of primary amines with internal alkynes catalyzed by Ru complexes is presented as a general atom-economy methodology with a broad scope of applications in the synthesis of N-heterocycles. Reactions proceed through regioselective C-H bond activation in 15 minutes under microwave irradiation or in 24 hours with conventional heating. The synthesis of 2,3,5-substituted pyridines, benzo[h]isoquinolines, benzo[g]isoquinolines, 8,9-dihydro-benzo[de]quinoline, 5,6,7,8-tetrahydroisoquinolines, pyrido[3,4g]isoquinolines, and pyrido[4,3g]isoquinolines is achievable depending on the starting primary amine used. DFT calculations on a benzylamine substrate support a reaction mechanism that consists of acetate-assisted C-H bond activation, migratory-insertion, and C-N bond formation steps that involve 28-30 kcalmol-1. The computational study is extended to additional substrates, namely, 1-naphthylmethyl-, 2-methylallyl-, and 2-thiophenemethylamines.
Flow synthesis of 2-methylpyridines via α-methylation
Manansala, Camille,Tranmer, Geoffrey K.
, p. 15797 - 15806 (2015/12/01)
A series of simple 2-methylpyridines were synthesized in an expedited and convenient manner using a simplified bench-top continuous flow setup. The reactions proceeded with a high degree of selectivity, producing α-methylated pyridines in a much greener fashion than is possible using conventional batch reaction protocols. Eight 2-methylated pyridines were produced by progressing starting material through a column packed with Raney nickel using a low boiling point alcohol (1-propanol) at high temperature. Simple collection and removal of the solvent gave products in very good yields that were suitable for further use without additional work-up or purification. Overall, this continuous flow method represents a synthetically useful protocol that is superior to batch processes in terms of shorter reaction times, increased safety, avoidance of work-up procedures, and reduced waste. A brief discussion of the possible mechanism(s) of the reaction is also presented which involves heterogeneous catalysis and/or a Ladenberg rearrangement, with the proposed methyl source as C1 of the primary alcohol.
Rh(III)-catalyzed decarboxylative coupling of acrylic acids with unsaturated oxime esters: Carboxylic acids serve as traceless activators
Neely, Jamie M.,Rovis, Tomislav
supporting information, p. 2735 - 2738 (2014/03/21)
α,β-Unsaturated carboxylic acids undergo Rh(III)-catalyzed decarboxylative coupling with α,β-unsaturated O-pivaloyl oximes to provide substituted pyridines in good yield. The carboxylic acid, which is removed by decarboxylation, serves as a traceless activating group, giving 5-substituted pyridines with very high levels of regioselectivity. Mechanistic studies rule out a picolinic acid intermediate, and an isolable rhodium complex sheds further light on the reaction mechanism.
Convenient procedure for the α-methylation of simple pyridines
Broering, Martin,Kleeberg, Christian
scheme or table, p. 3672 - 3682 (2009/04/03)
A convenient and straightforward laboratory procedure is presented for a highly selective mono-α-methylation of pyridines without reactive functional groups. The methylating agent is probably carbon monoxide/dihydrogen generated in situ from a high-boiling alcohol on a metal surface. The reaction is catalyzed by a Raney nickel catalyst at ambient pressure, which renders the protocol practicable in standard organic laboratories. The intrinsically high reaction temperature and long reaction times restrict the application to pyridine derivatives with less reactive substituents. The outcome of the reaction can be rationalized by the assumption of a simple heterogeneous mechanism. Copyright Taylor & Francis Group, LLC.
Inhibitors of cell proliferation, angiogenesis, fertility, and muscle contraction
-
, (2008/06/13)
The invention concerns inhibitors of cell proliferation, angiogenesis, fertility, and muscle contraction, characterized by formula I wherein, X, Y and Z independently represent C or N; ------ is an optional double bond; n is 0 or 1; R1, R2, and R4 independently represent hydrogen, a chemical bond, C1-10 alkyl; C2-10 alkenyl; C2-10 alkinyl; aryl; aryl-C1-10 alkyl; C3-10 heterocyclyl; C5-10 heteroaryl; halo, CF3; NO2; NHC(O)R*, OR, said alkyl, alkenyl, alkinyl, aryl, arylalkyl, heterocyclyl, or heteroaryl being optionally substituted; R3, R5, and R6 independently represent hydrogen, C1-10alkyl; C2-10 alkenyl; C2-10 alkinyl; aryl; aryl-C1-10alkyl; C3-10 heterocyclyl; C5-10 heteroaryl; halo, CF3; NO2; NHC(O)R*, OR, said alkyl, alkenyl, alkinyl, aryl, heterocyclyl, or heteroaryl being optionally substituted; or R5 and R6 together form a 5- or 6-member aryl, heterocyclyl or heteroaryl group; R is hydrogen or C1-6 alkyl; R* is hydrogen, or C1-6 alkyl, or OH, wherein the optional substituents are preferably selected from the group of one to three OH, C1-6 alkyl, halo, NO2, C1-6 alkoxy, and CF3, or a pharmaceutically acceptable salt thereof.
A method for producing pyridine bases
-
Page 2, (2008/06/13)
A method for producing pyridine bases which comprises reacting in a gas-phase an aliphatic aldehyde, aliphatic ketone or mixture thereof with ammonia in the presence of a zeolite comprising titanium and/or cobalt and silicon as zeolite constituent elements in which the atomic ratio of silicon to titanium and/or cobalt is about 5 to 1000 gives improved yield.
Synthesis of alkyl- and aryl-substituted pyridines from (α,β-unsaturated) imines or oximes and carbonyl compounds
Vijn,Arts,Green,Castelijns
, p. 573 - 578 (2007/10/02)
Reaction of a variety of (α,β-unsaturated) imines or oximes with aliphatic aldehydes or cyclic ketones in the presence of a secondary amine afforded alkyl-, and/or aryl-, and/or cycloalkyl-substituted pyridines. To explain their formation, a hetero Diels-Alder reaction has been postulated, in which an 1-aza-1,3-butadiene reacts with an in situ generated enamine.
Process for preparing 2-methyl-3,5-dialkylpyridines by dealkylation with sulfur
-
, (2008/06/13)
A process for dealkylating the 2-position on a trisubstituted pyridine derivative having the formula STR1 where R1 is a straight chain alkyl group from about C2 -C5 and where R2 and R3 are alkyl, aryl or aralkyl groups up to about C10, comprising the step of reacting said pyridine derivative at reflux with excess sulfur. Of particular note is the preparation of 2,3,5-trimethylpyridine including the initial preparation of its 2-ethyl precursor by the Chichibabin reaction of propionaldehyde and ammonia.
2,4-dichloro-3,5,6-trimethylpyridine
-
, (2008/06/13)
A method for the preparation of 2,3,5-trimethylpyridine and some of its derivatives.
