298-57-7Relevant academic research and scientific papers
Oxidative Rearrangement of MIDA (N-Methyliminodiacetic Acid) Boronates: Mechanistic Insights and Synthetic Applications
Kaldas, Sherif J.,Tien, Chieh-Hung,Gomes, Gabriel Dos Passos,Meyer, Stephanie,Sirvinskas, Martynas,Foy, Hayden,Dudding, Travis,Yudin, Andrei K.
supporting information, p. 324 - 328 (2021/01/26)
Herein we report that coordinative hemilability allows the MIDA (N-methyliminodiacetic acid) nitrogen to behave as a nucleophile and intramolecularly intercept palladium π-allyl intermediates. A mechanistic investigation indicates that this rearrangement proceeds through an SN2-like displacement at tetrasubstituted boron to furnish novel DABN boronates. Oxidative addition into the N-C bond of the DABN scaffold furnishes borylated π-allyl intermediates that can then be trapped with a variety of nucleophiles, including in a three-component coupling.
Allyl coupling reaction method and application thereof
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Paragraph 0304-0308, (2021/08/25)
The invention discloses a novel allyl coupling reaction method which takes an allyl thianthene salt as an allylation reagent and respectively takes a carboxylic acid compound. An allylated coupling product is obtained by reacting a substrate with a base in the presence of a base, or directly with a carboxylate compound, an aromatic hydrocarbon/heterocyclic hydrocarbon as a substrate, and at room temperature. The preparation method is mild in condition and free of transition metal participation, can efficiently realize preparation of various allyl ester, allyl substituted amine and allyl substituted aromatic hydrocarbon/heterocyclic hydrocarbon compound, and has an ideal application prospect in the fields of fine chemical engineering, material science and pharmacy.
Scalable preparation of stable and reusable silica supported palladium nanoparticles as catalysts for N-alkylation of amines with alcohols
Alshammari, Ahmad S.,Natte, Kishore,Kalevaru, Narayana V.,Bagabas, Abdulaziz,Jagadeesh, Rajenahally V.
, p. 141 - 149 (2020/01/06)
The development of nanoparticles-based heterogeneous catalysts continues to be of scientific and industrial interest for the advancement of sustainable chemical processes. Notably, up-scaling the production of catalysts to sustain unique structural features, activities and selectivities is highly important and remains challenging. Herein, we report the expedient synthesis of Pd-nanoparticles as amination catalysts by the reduction of simple palladium salt on commercial silica using molecular hydrogen. The resulting Pd-nanoparticles constitute stable and reusable catalysts for the synthesis of various N-alkyl amines using borrowing hydrogen technology without the use of any base or additive. By applying this Pd-based catalyst, functionalized and structurally diverse N-alkylated amines as well as some selected drug molecules were synthesized in good to excellent yields. Practical and synthetic utility of this Pd-based amination protocol has been demonstrated by upscaling catalyst preparation and amination reactions to several grams-scales as well as recycling of catalyst. Noteworthy, this Pd-catalyst preparation has been up-scaled to kilogram scale and catalysts prepared in both small (1 g) and large-scale (kg) exhibited similar structural features and activity.
Metal-Organic Capsules with NADH Mimics as Switchable Selectivity Regulators for Photocatalytic Transfer Hydrogenation
Wei, Jianwei,Zhao, Liang,He, Cheng,Zheng, Sijia,Reek, Joost N. H.,Duan, Chunying
, p. 12707 - 12716 (2019/09/04)
Switchable selective hydrogenation among the groups in multifunctional compounds is challenging because selective hydrogenation is of great interest in the synthesis of fine chemicals and pharmaceuticals as a result of the importance of key intermediates. Herein, we report a new approach to highly selectively (>99%) reducing C=X (X = O, N) over the thermodynamically more favorable nitro groups locating the substrate in a metal-organic capsule containing NADH active sites. Within the capsule, the NADH active sites reduce the double bonds via a typical 2e- hydride transfer hydrogenation, and the formed excited-state NAD+ mimics oxidize the reductant via two consecutive 1e- processes to regenerate the NADH active sites under illumination. Outside the capsule, nitro groups are highly selectively reduced through a typical 1e- hydrogenation. By combining photoinduced 1e- transfer regeneration outside the cage, both 1e- and 2e- hydrogenation can be switched controllably by varying the concentrations of the substrates and the redox potential of electron donors. This promising alternative approach, which could proceed under mild reaction conditions and use easy-to-handle hydrogen donors with enhanced high selectivity toward different groups, is based on the localization and differentiation of the 2e- and 1e- hydrogenation pathways inside and outside the capsules, provides a deep comprehension of photocatalytic microscopic reaction processes, and will allow the design and optimization of catalysts. We demonstrate the advantage of this method over typical hydrogenation that involves specific activation via well-modified catalytic sites and present results on the high, well-controlled, and switchable selectivity for the hydrogenation of a variety of substituted and bifunctional aldehydes, ketones, and imines.
Preparation method and application of adjustable metal organic cage compound for efficiently selective catalytic reduction of nitrobenzaldehyde
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Paragraph 0039-0040, (2019/12/02)
The invention belongs to the technical field of fine chemical engineering. The invention relates to a preparation method and application of an adjustable metal organic cage compound for efficient selective catalytic reduction of nitrobenzaldehyde. According to the preparation method, M in a transition metal salt is used as a node and L is used as a ligand for reaction to prepare the metal organic cage compound, and the synthetic route is as follows: M + L- to M-L; wherein the ligand L is selected from H2FPB; the transition metal salt is selected from one of ferrous perchlorate, cobalttetrafluoroborate, nickel perchlorate or zinc tetrafluoroborate. The metal organic cage compound prepared by the method is low in raw material price and high in yield, and the obtained compound is stable in chemical property and easy to put into practical application. As a target compound M-FPB, the adjustable metal organic cage compound shows that the selectivity of the compound M-FPB can reach 99% in the aspects of reduction of p-nitrobenzaldehyde to prepare p-nitrobenzyl alcohol, one-step synthesis of cinnarizine by reduction catalysis of cinnamyl aldehyde and reduction of p-nitrobenzaldehyde to prepare p-aminobenzaldehyde.
Palladium-Based Hydroamination Catalysts Employing Sterically Demanding 3-Iminophosphines: Branched Kinetic Products by Prevention of Allylamine Isomerization
Thakuri, Rajendr S.,Schmidt, Joseph A. R.
, p. 1917 - 1927 (2019/05/21)
A new allylpalladium triflate catalyst with a dimesitylphosphine moiety was synthesized, isolated, and characterized. The greatly increased steric bulk on the phosphine of this palladium catalyst inhibited product isomerization, which is often observed after hydroamination of terminal allenes with secondary amines. The considerably reduced rate of isomerization facilitated the isolation of many previously unknown branched allylamines, products that were inaccessible when using other, more active 3-iminophosphine palladium catalysts.
Practical regio- and stereoselective azidation and amination of terminal alkenes
Ojo, Olatunji S.,Miranda, Octavio,Baumgardner, Kyle C.,Bugarin, Alejandro
supporting information, p. 9354 - 9358 (2019/01/03)
There is significant interest in developing more rapid and efficient production of nitrogen-containing allylic compounds, as widely used in various syntheses. This work reports a variety of allylic azides and allylic amines synthesized by an efficient, new one-pot protocol that employs readily available terminal alkenes as starting materials. This method is highly regio- and stereoselective, affording the linear (E)-isomer, under metal-free conditions. This process tolerates several functional groups including halogen-containing molecules; it is general for azides and amine nucleophiles; and, adducts were obtained in good yields.
Tertiary amine synthesis: Via reductive coupling of amides with Grignard reagents
Xie, Lan-Gui,Dixon, Darren J.
, p. 7492 - 7497 (2017/10/30)
A new iridium catalyzed reductive coupling reaction of Grignard reagents and tertiary amides affording functionalised tertiary amine products via an efficient and technically-simple one-pot, two-stage experimental protocol, is reported. The reaction-which can be carried out on gram-scale using as little as 1 mol% Vaska's complex [IrCl(CO)(PPh3)2] and TMDS as the terminal reductant for the initial reductive activation step-tolerates a broad range of tertiary amides from (hetero)aromatic to aliphatic (branched, unbranched and formyl) and a wide variety of alkyl (linear, branched), vinyl, alkynyl and (hetero)aryl Grignard reagents. The new methodology has been applied directly to bioactive molecule synthesis and the high chemoselectivity of the reductive coupling of amide has been exploited in late stage functionalization of drug molecules. This reductive functionalisation of tertiary amides provides a new and practical solution to tertiary amine synthesis.
Direct use of allylic alcohols and allylic amines in palladium-catalyzed allylic amination
Jing, Jiangyan,Huo, Xiaohong,Shen, Jiefeng,Fu, Jingke,Meng, Qinghua,Zhang, Wanbin
supporting information, p. 5151 - 5154 (2017/07/12)
Allylic alcohols and allylic amines were directly utilized in a Pd-catalyzed hydrogen-bond-activated allylic amination under mild reaction conditions in the absence of any additives. The cooperative action of a Pd-catalyst and a hydrogen-bonding solvent is most likely responsible for its high reactivity. The catalytic system is compatible with a variety of functional groups and can be used to prepare a wide range of linear allylic amines in good to excellent yields. Furthermore, this methodology can be easily applied to the one-step synthesis of two drugs, cinnarizine and naftifine, on a gram scale.
Mitsunobu Reaction Using Basic Amines as Pronucleophiles
Huang, Hai,Kang, Jun Yong
, p. 6604 - 6614 (2017/07/15)
A novel protocol for extending the scope of the Mitsunobu reaction to include amine nucleophiles to form C-N bonds through the utilization of N-heterocyclic phosphine-butane (NHP-butane) has been developed. Both aliphatic alcohols and benzyl alcohols are suitable substrates for C-N bond construction. Various acidic nucleophiles such as benzoic acids, phenols, thiophenol, and secondary sulfonamide also provide the desired products of esters, ethers, thioether, and tertiary sulfonamide with 43-93% yields. Importantly, C-N bond-containing pharmaceuticals, Piribedil and Cinnarizine, have been synthesized in one step from the commercial amines under this Mitsunobu reaction system.
