80781-18-6Relevant academic research and scientific papers
Nickel Phosphite/Phosphine-Catalyzed C-S Cross-Coupling of Aryl Chlorides and Thiols
Jones, Kieran D.,Power, Dennis J.,Bierer, Donald,Gericke, Kersten M.,Stewart, Scott G.
supporting information, p. 208 - 211 (2018/01/17)
A method for the coupling of aryl chlorides and thiophenols using an air-stable nickel(0) catalyst is described. This thioetherification procedure can be effectively applied to a range of electronically diverse aryl/heteroaryl chlorides without more expensive metal catalysts such as palladium, iridium, or ruthenium. This investigation also illustrates both, a variety of thiol coupling partners and, in certain cases, the use of Cs2CO3.
Use of highly active palladium-phosphinous acid catalysts in Stille, Heck, amination, and thiation reactions of chloroquinolines
Wolf, Christian,Lerebours, Rachel
, p. 7077 - 7084 (2007/10/03)
An efficient synthetic route toward a variety of 2,4-disubstituted quinolines has been developed. Alkylation and arylation of 4-chloroquinoline using organolithium reagents proceed with high regioselectivity in position 2 under cryogenic conditions. The intermediate 1,2-dihydro-4-chloro-quinoline derivatives are unstable to air and are easily oxidized to the corresponding 2-substituted 4-chloroquinolines in high yields. Highly active palladium-phosphinous acid catalysts POPd, POPd1, and POPd2 have been employed in Stille cross-couplings of quinaldine with arylstannanes and in Heck additions of various 2-substituted 4-chloroquinolines to tert-butyl acrylate. In particular, POPd combines high catalytic activity for cross-coupling reactions with simplicity of use due to its stability to air. Utilizing CsF in POPd-catalyzed Stille couplings further increased the reactivity of arylstannanes, which was attributed to the fluorophilicity of organotin compounds. Basic additives were found to exhibit a significant effect on the yields of the POPd-promoted Heck reactions. In general, dicyclohexylmethylamine affords superior results than NaOAc, Cs2CO3, or t-BuOK. POPd was also found to tolerate amine and thiol substrates and proved to promote carbon-heteroatom bond formation of chloroquinoline derivatives with aliphatic and aromatic amines and thiols, respectively.
Nucleophilic Displacement of Primary Amino Groups via 1-Substituted 4-Tosylimidazoles
Taylor, Edward C.,LaMattina, John L.,Tseng, Chi-Ping
, p. 2043 - 2047 (2007/10/02)
Two methods are discribed for the replacement of primary amino groups, situated either α or γ to a heterocyclic nitrogen atom, by ethoxy, alkylthio, and arylthio substituents, by Wittig reagents, and by hydrogen.Both methods involve transformation of the primary amino group into a nucleofugic pendant heterocycle.The first converts the primary amino group into a 5-phenyl-1-tetrazolyl substituent by benzoylation, formation of the imidoyl chloride, and reaction with sodium azide, while the second converts the primary amino group into a 1-(4-tosylimidazolyl) substituent by reaction with triethyl orthoformate and acid to give the (ethoxymethylene)amino derivative, which is then condensed with tosylmethyl isocyanide (TosMIC) anion.The 1-(4-tosylimidazolyl) substituent is shown to be more susceptible to nucleophilic displacement by a wider range of nucleophiles.
