4442-85-7Relevant academic research and scientific papers
Zirconium-hydride-catalyzed site-selective hydroboration of amides for the synthesis of amines: Mechanism, scope, and application
Han, Bo,Jiao, Haijun,Wu, Lipeng,Zhang, Jiong
, p. 2059 - 2067 (2021/09/02)
Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective. In this respect, catalytic deoxygenative amide reduction has proven to be promising but challenging, as this approach necessitates selective C–O bond cleavage. Herein, we report the selective hydroboration of primary, secondary, and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst, Zr-H, for accessing diverse amines. Various readily reducible functional groups, such as esters, alkynes, and alkenes, were well tolerated. Furthermore, the methodology was extended to the synthesis of bio- and drug-derived amines. Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C–N bond cleavage-reformation process, followed by C–O bond cleavage.
Efficient preparation and application of monodisperse palladium loaded graphene oxide as a reusable and effective heterogeneous catalyst for suzuki cross-coupling reaction
Diler, Fatma,Burhan, Hakan,Genc, Hayriye,Kuyuldar, Esra,Zengin, Mustafa,Cellat, Kemal,Sen, Fatih
, (2019/11/29)
A homogeneously dispersed graphene oxide supported palladium nanomaterial (Pd?GO) has been successfully synthesized and used as a catalyst in cross-coupling reactions at room temperature. Various analytical techniques such as X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) were used to characterize the monodisperse Pd?GO. Monodisperse Pd?GO nanomaterials were used for the cross-coupling reactions which brought together organic molecules with functional significance. This catalyst showed superior catalytic activity and stability for these coupling reactions. High product yields, short reaction times and mild reaction conditions, obtained by the using of developed catalysts. Importantly, the catalyst can be used at least five experiments successfully without losing its efficiency.
Remote Directed Isocyanation of Unactivated C(sp3)-H Bonds: Forging Seven-Membered Cyclic Ureas Enabled by Copper Catalysis
Zhang, Hongwei,Tian, Peiyuan,Ma, Lishuang,Zhou, Yulu,Jiang, Cuiyu,Lin, Xufeng,Xiao, Xiao
supporting information, p. 997 - 1002 (2020/02/15)
Reported herein is an unprecedented copper-catalyzed site-selective ?-C(sp3)-H bonds activation of aliphatic sulfonamides for constructing the synthetically useful seven-membered N-heterocycles. A key to success is the use of in-situ-formed amide radicals, to activate the inert C(sp3)-H bond, and inexpensive TMSNCO, as a coupling reagent under mild conditions. To the best of our knowledge, this represents the first use of alkylamine derivatives as a five-membered synthon to prepare a seven-membered N-heterocycles.
Copper-Catalyzed Amide Radical-Directed Cyanation of Unactivated Csp3-H Bonds
Zhang, Hongwei,Zhou, Yulu,Tian, Peiyuan,Jiang, Cuiyu
supporting information, (2019/03/19)
A method for site-selective intermolecular δ/?-Csp3-H cyanation of aliphatic sulfonamides is developed using TsCN as the cyanating reagent, catalyzed by a Cu(I)/phenanthroline complex. The mild, expeditious, and modular protocol allows efficient remote Csp3-H cyanation with good functional group tolerance and high regioselectivity. Mechanistic studies indicate that the reaction might proceed through a Cu(I)-mediated N-F bond cleavage to generate an amidyl radical, 1,5-HAT, and cyano group transfer of the resulting carbon radical with TsCN.
One-pot anti-markovnikov hydroamination of unactivated alkenes by hydrozirconation and amination
Strom, Alexandra E.,Hartwig, John F.
, p. 8909 - 8914 (2013/09/24)
A one-pot anti-Markovnikov hydroamination of alkenes is reported. The synthesis of primary and secondary amines from unactivated olefins was accomplished in the presence of a variety of functional groups. Hydrozirconation, followed by amination with nitrogen electrophiles, provides exclusive anti-Markovnikov selectivity. Most products are isolated in high yields without the use of column chromatography.
Structure-selectivity relationship in the chemoselective hydrogenation of unsaturated nitriles
Kukula, Pavel,Koprivova, Klara
, p. 161 - 171 (2007/10/03)
Several unsaturated nitriles of various structures (cinnamonitrile, cyclohex-1-enyl-acetonitrile, acrylonitrile, 3,3-dimethyl-acrylonitrile, geranylnitrile, and 2- and 3-pentenenitrile) with different substituents at the double bond were hydrogenated over
Chemoselective hydrogenation of α,β-unsaturated nitriles
Kukula, Pavel,Studer, Martin,Blaser, Hans-Ulrich
, p. 1487 - 1493 (2007/10/03)
The chemoselective hydrogenation of cinnamonitrile to 3-phenylallylamine proceeds with up to 80% selectivity at conversions of > 90% with Raney cobalt and up to 60% selectivity with Raney nickel catalysts. Best results were obtained with a doped Raney cobalt catalyst (RaCo/Cr/Ni/Fe 2724) in ammonia saturated methanol at 100°C and 80 bar. Major problems are the formation of hydrocinnamonitrile and of secondary amines, and overreduction to 3-phenylpropylamine. Important parameters are the catalyst type and composition, the solvent type and the presence and concentration of ammonia. The catalytic system tolerates functional groups like OH, OMe, Cl, C=O, but not aromatic nitro groups. Preliminary experiments indicate that other unsaturated nitriles with di- or trisubstituted C=C bonds are also suitable substrates.
Inhibitors of protein isoprenyl transferases
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, (2008/06/13)
Compounds having the formula or a pharmaceutically acceptable salt thereof wherein R1is (a) hydrogen, (b) loweralkyl, (c) alkenyl, (d) alkoxy, (e) thioalkoxy, (f) halo, (g) haloalkyl, (h) aryl-L2—, and (i) heterocyclic-L2—; R2is selected from (a) (b) —C(O)NH—CH(R14)—C(O)OR15, (d) —C(O)NH—CH(R14)—C(O)NHSO2R16, (e) —C(O)NH—CH(R14)-tetrazolyl, (f) —C(O)NH-heterocyclic, and (g) —C(O)NH—CH(R14)—C(O)NR17R18; R3is substituted or unsubstituted heterocyclic or aryl, substituted or unsubstituted cycloalkyl or cycloalkenyl, and —P(W)RR3RR3′; R4is hydrogen, lower alkyl, haloalkyl, halogen, aryl, arylakyl, heterocyclic, or (heterocyclic)alkyl; L1is absent or is selected from (a) —L4—N(R5)—L5—, (b) —L4—O—L5—, (c) —L4—S(O)n—L5— (d) —L4—L6—C(W)—N(R5)—L5—, (e) —L4—L6—S(O)m—N(R5)—L5—, (f) —L4—N(R5)—C(W)—L7—L5—, (g) —L4—N(R5)—S(O)p—L7—L5—, (h) optionally substituted alkylene, (i) optionally substituted alkenylene, (j) optionally substituted alkynylene (k) a covalent bond, (l) and (m) are inhibitors of protein isoprenyl transferases. Also disclosed are protein isoprenyl transferase inhibiting compositions and a method of inhibiting protein isoprenyl transferases.
