6041-28-7Relevant academic research and scientific papers
Rhodium(III)-catalyzed oxadiazole-directed alkenyl C-H activation for synthetic access to 2-acylamino and 2-amino pyridines
Yang, Fan,Yu, Jiaojiao,Liu, Yun,Zhu, Jin
supporting information, p. 9978 - 9987 (2018/05/31)
We report herein a Rh(III)-catalyzed alkenyl C-H activation protocol for the coupling of oxadiazoles with alkynes and synthesis of 2- acylamino and 2-amino pyridines, an important heterocyclic scaffold for various naturals products and synthetic pharmaceuticals bearing a readily reacting functional group. The selective protection/deprotection of amino groups through simple solvent switching, good functional group compatibility, superior product yield, and high regioselectivity are some of the notable synthetic features witnessed in this reaction protocol.
Preparation method of trans-alpha, beta-unsaturated nitriles compound
-
Paragraph 0063-0065, (2017/05/18)
The invention relates to a preparation method of a trans-alpha, beta-unsaturated nitriles compound. The method comprises the following steps: uniformly mixing a benzyl alcohol compound, acetonitrile, a promoter and alkali, and carrying out reflux reaction completely to obtain reaction liquid; carrying out conventional extraction, drying, concentration and column chromatographic separation on the reaction liquid in sequence to obtain the trans-alpha, beta-unsaturated nitriles compound. The preparation method belongs to double-component one-boiler reaction, so that conditions are relatively mild, and raw materials are easy to prepare and readily available; the operation is simple, the yield is relatively high, and greenness, environment friendliness and economy can be realized; large-scale production can be realized; the preparation method has an extremely good application potential on the aspect of fine chemicals, and has a relatively good industrial application prospect.
A Catalytic Peterson-like Synthesis of Alkenyl Nitriles
Lanari, Daniela,Alonzi, Matteo,Ferlin, Francesco,Santoro, Stefano,Vaccaro, Luigi
supporting information, p. 2680 - 2683 (2016/06/15)
A heterogeneous fluoride catalyst was found to enable the straightforward formation of alkenyl nitriles from the reaction of aldehydes and simple or substituted acetonitriles, in the presence of commercially available silazanes and in solvent-free conditions. The protocol afforded the products in good to excellent yields with selectivity values dependent on the nature of the substrates. It represents an alternative to classic approaches using stoichiometric strong bases, and the catalyst can be easily recovered and reused for consecutive cycles.
Immobilized NNN Pd-complex on magnetic nanoparticles: Efficient and reusable catalyst for Heck and Sonogashira coupling reactions
Dehghani Firuzabadi, Fahimeh,Asadi, Zahra,Panahi, Farhad
, p. 101061 - 101070 (2016/11/09)
A highly efficient and easily recyclable magnetic nanoparticle supported palladium catalyst was developed and applied in the Heck and Sonogashira reactions in order to show its catalytic applicability in Pd-catalyzed C-C coupling protocols. The catalyst was prepared using a simple chemical process. First, the prepared Fe3O4@SiO2 nanoparticles were reacted with (3-chloropropyl)-trimethoxysilane (3-CPTMS) in order to synthesis chloro-functionalized magnetic nanoparticles (CPS-MNPs). The substitution reaction of synthetic NNN ligand with CPS-MNPs yields the production of CPS-MNPs-NNN ligand. Finally, immobilization of palladium species on CPS-MNPs-NNN ligand surface afforded CPS-MNPs-NNN-Pd catalyst. The structure and morphology of the prepared nanocatalyst was characterized using various methods such as SEM, TEM, XPS, EDX, CHN, ICP, XRD, FT-IR and VSM techniques. The TEM images show that the sizes of the palladium catalyst are in the range of 8-15 nm. The Heck and Sonogashira coupling reactions were performed in the presence of a catalytic amount of this catalyst system (0.5 mol%) and good yields of products were obtained. Due to the magnetic nature of the catalyst it can be separated from the reaction mixture easily by applying an external magnetic field. Heterogeneity tests affirmed that the catalytic activity stayed indefectible during multiple reaction cycles.
Cascade reaction of propargylic alcohols with hydroxylamine hydrochloride: facile synthesis of α,β-unsaturated oximes and nitriles
Zhang, Qi,Zhang, Linjing,Tang, Chaojun,Luo, Huan,Cai, Xuediao,Chai, Yonghai
, p. 6935 - 6942 (2016/10/14)
We have developed an easy and practical method for the synthesis of α,β-unsaturated oximes and nitriles from readily available propargylic alcohols with hydroxylamine hydrochloride (NH2OH·HCl) under metal-free conditions. By using or not using p-toluenesulfonyl chloride (p-TsCl) as the dehydrating promoter, the desired nitriles or oximes could be obtained, respectively via a three-step one-pot or two-step one-pot process in moderate to excellent yields with good functional group compatibility.
Cu-catalyzed debrominative cyanation of gem-dibromoolefins: A facile access to α,β-unsaturated nitriles
Ahuja, Brij Bhushan,Sudalai, Arumugam
, p. 5918 - 5923 (2015/06/02)
An efficient catalytic route for the synthesis of α,β-unsaturated nitriles from easily accessible gem-dibromoolefins has been developed. The method utilized inexpensive reagents such as Cu2O as a catalyst, l-proline as a ligand and NaCN as a cyanide source to afford α,β-unsaturated nitriles in high yields (62-86%). A deuterium exchange study has shown that one of the bromide atoms of gem-dibromoolefins exchanges with cyanide while the other with a deuterium atom.
Dual [Fe+Phosphine] catalysis: Application in catalytic wittig olefination
Rommel, Susanne,Belger, Christian,Begouin, Jeanne-Marie,Plietker, Bernd
, p. 1292 - 1301 (2015/04/27)
Iron hydride complexes of the general formula P2Fe(NO)CO)H are highly active catalysts for the hydrosilylation of aldehydes or ketones and phosphine oxides. Depending on the solvent, the in situ reduction of the phosphine oxide can be faster than the corresponding hydrosilylation of a carbonyl group. This unusual activity was used within the context of catalytic Wittig olefination. Picture perfect: Iron hydride complexes of the general formula P2Fe(NO)CO)H are highly active catalysts for the hydrosilylation of aldehydes or ketones and phosphine oxides. Depending on the solvent, the in situ reduction of the phosphine oxide can be faster than the corresponding hydrosilylation of a carbonyl group. This unusual activity is used within the context of catalytic Wittig olefination. EWG=Electron-withdrawing group.
METHODS FOR PHOSPHINE OXIDE REDUCTION IN CATALYTIC WITTIG REACTIONS
-
Page/Page column 37; 43; 45, (2014/09/29)
A method for increasing the rate of phosphine oxide reduction, preferably during a Wittig reaction comprising use of an acid additive is provided. A room temperature catalytic Wittig reaction (CWR) the rate of reduction of the phosphine oxide is increased due to the addition of the acid additive is described. Furthermore, the extension of the CWR to semi-stabilized and non-stabilized ylides has been accomplished by utilization of a masked base and/or ylide-tuning.
Bronsted acid mediated nitrogenation of propargylic alcohols: An efficient approach to alkenyl nitriles
Huang, Xiaoqiang,Jiao, Ning
supporting information, p. 4324 - 4328 (2014/06/23)
A novel and efficient approach to alkenyl nitriles from readily available propargylic alcohols has been developed. This nitrogenation reaction is transition-metal-free and could be conducted under air at ambient temperature, which makes this protocol promising and practical. Moreover, NH4Br is disclosed as an efficient additive to promote the stereoselectivity of this reaction. the Partner Organisations 2014.
Breaking the ring through a room temperature catalytic wittig reaction
O'Brien, Christopher J.,Lavigne, Florie,Coyle, Emma E.,Holohan, Andrew J.,Doonan, Bryan J.
supporting information, p. 5854 - 5858 (2013/06/27)
One ring no longer rules them all: Employment of 2.5-10 mol % of 4-nitrobenzoic acid with phenylsilane led to the development of a room temperature catalytic Wittig reaction (see scheme). Moreover, these enhanced reduction conditions also facilitated the use of acyclic phosphine oxides as catalysts for the first time. A series of alkenes were produced in moderate to high yield and selectivity. Copyright
