An Efficient Palladium-Thiourea Catalysed Heck Cross-Coupling Reaction for Molecular Electronic Interest

Abstract

The synthesis and utilization of C-C bonds formation are concerned about the key steps for the building of several conducting molecular electronics involving many asymmetric catalysts approached, which is an essential task that most researchers would ignore in preparing these materials to enhance the production yield of cross-coupling materials. Despite the enormous progress, there still remains a great demand for economic and practicable cross-coupling processes involving ultra-low catalyst loadings with high turnover numbers due to the employment of conventional metal catalyst. Thus, there has been an excessive interest to cultivate non-phosphine palladium catalysts for excellent achievement of activity, stability, and substrate tolerance which permit the coupling reactions to be conducted under mild reaction condition at ambient atmosphere. In this contribution, N-(4-nitrophenylcarbamothioyl)-N'-(4-methylbenzoyl) thiourea (LT1) and its metal complex of MLT1 featuring Pd (II) have been successfully characterised via typical spectroscopic methods namely; Infrared (IR) spectroscopy, Ultraviolet-visible (UV-Vis) spectroscopy, CHNS elemental analysis, and Nuclear Magnetic Resonance ( 1 H and 13 C NMR). In turn, catalytic studies of palladium catalyst (MLT1) were tested for its homogenous catalytic activity in Heck cross-coupling reaction. The reaction was monitored by Gas Chromatography-Flame Ionisation Detector (GC-FID). Results reveal that MLT1 exhibits 100% of conversion starting material into a cross-coupling product, which was alkene-based compound. Abstrak Palladium-Tiourea Yang Efisien Sebagai Katalis Reaksi Gandengan Silang Heck Untuk Molekul Elektronik.Sintesis dan penggunaan pembentukan ikatan C-C perlu diperhatikan sebagai langkah utama untuk membina beberapa molekul elektronik terkonduksi yang melibatkan banyak katalis-katalis asimetris, yang merupakan tugas yang sering diabaikan oleh kebanyakan peneliti dalam menyediakan bahan-bahan ini untuk meningkatkan pengeluaran hasil bahan gandengan silang. Meskipun telah banyak perkembangan dalam hal ini, masih ada permintaan yang tinggi untuk proses gandengan silang yang lebih ekonomis dan praktis yang hanya melibatkan pembekalan katalis yang sangat rendah dengan hasil perolehan yang tinggi dengan penggunaan katalis logam biasa. Oleh karena itu, terdapat banyak kepentingan untuk menghasilkan katalis paladium tanpa fosfina untuk pencapaian yang cemerlang dari segi aktivitas, kestabilan dan toleransi substrat yang membenarkan reaksi gandengan silang yang dijalankan dalam keadaan reaksi sederhana pada keadaan atmosfer tertentu. Dalam kajian ini, N-(4-nitrofenilcarbamotionil)-N'-(4-metilbenzoil) tiourea (LT1) dan kompleks logamnya yaitu MLT1 menampilkan Pd(II) telah berhasil dicirikan melalui kaidah spektroskopi yang biasa yaitu spektroskopi sinar inframerah (IR), spektroskopi Ultra-Lembayung Sinar Nampak (UV-Vis), analisis unsur CHNS dan Resonan Magnetik Nukleus ( 1 H dan 13 C NMR). Selanjutnya, tindak balas ini dipantau menggunakan Gas Chromatography-Fla...

Palladium(II) Picoline Thiourea Complex as Homogenous Catalyst in Heck Cross-Coupling Reaction in the Formation of C=C Bond

“…Due to these existing problems, researchers have actively carrying out attempts on discovery of phosphine-free ligands such as N-heterocyclic carbenes [10][11] and sulfur-containing ligands [12] to be applied in metal-catalyzed synthetic reactions in order to achieve good stability and substrate tolerance which allow the coupling reaction to be conducted under mild condition or at ambient environment. Recently, thiourea system has attracted considerable attention to be used in catalysis system [13][14][15] due to its unique properties such as able to coordinate with various transition metal ions as monodentate or bidentate ligands [16][17], great tunability by varying substituents on the nitrogen and stable in moisture. By considering their physical and chemical properties, thiourea derivatives have been introduced to be used as ligand in palladium complexes in order to replace the functionality of phosphine in catalysis system.…”

Synthesis and Characterization of Polymers Bearing Thiourea Moiety and StudyTheir Efficiency in Removing Heavy Metal Ions from Aqueous Solutions

“…Moreover, they have a large tendency for the formation of hydrogen bonding [8]. Their derivatives have a wide range of applications, such as potential therapeutic agents [9], in agrochemical materials [10], anti-corrosion inhibitors [11], and other important uses [12,13]. They are often synthesized by alkyl, aryl, and aroyl isothiocyanates [14].…”