Arylation of Amines and Monoarylation of Symmetrical Diamines in the Presence of Brine Solution with Diheteroaryl Halides

A simple, scalable, ligand-free, and metal-free protocol for arylation of amines and monoarylation of symmetrical diamines with diheteroaryl halides in the presence of brine solution has been developed. The protocol has broad structural applicability for chemoselective monoarylation of a wide variety of symmetrical, cyclic, and acyclic aliphatic diamines. The protocol is also applicable for selective arylation of aliphatic amine in the presence of aromatic amine.     

Phenylation of Organic Derivatives of Mercury,Silicon, Tin,and Bismuth with Pentaphenylantimony and Pentaphenylphosphorus

Pentaphenylantimony and -phosphorus react with arylmercury chlorides in toluene at room temperature to give diaryl derivatives of mercury in yields of up to 95%. The reactions of pentaphenylantimony and -phosphorus with silicon and tin halides involve arylation of the latter in yields of up to 79%. The products of the reaction of pentaphenylphosphorus with triphenylbismuth dihalides are tetraphenylphosphorus halides, triphenylbismuth, and halobenzene.     

Transition-metal-free nucleophilic allylic substitutions of Morita–Baylis–Hillman bromides with aliphatic and aromatic amines

A simple protocol for the preparation of functionalized allylic amines under mild, transition-metal-free conditions from the reaction of Morita–Baylis–Hillman (MBH) bromides with amines is described herein. The treatment of the MBH bromides with various amines in the presence of NaI and Et₃N in aqueous acetone solution and at room temperature affords the corresponding functionalized allyl amines in moderate to good yields (45–87%). The reaction is rapid and carried out at room temperature.     

Direct Arylation of α‐Amino C(sp3)‐H Bonds by Convergent Paired Electrolysis

A metal‐free convergent paired electrolysis strategy to synthesize benzylic amines through direct arylation of tertiary amines and benzonitrile derivatives at room temperature has been developed. This TEMPO‐mediated electrocatalytic reaction makes full use of both anodic oxidation and cathodic reduction without metals or stoichiometric oxidants, thus showing great potential and advantages for practical synthesis. This convergent paired electrolysis method provides a straightforward and powerful means to activate C?H bonds and realize cross‐coupling with cathodically generated species.     

Facile N‐Alkylation/N′‐Arylation Process: A Direct Approach to Aromatic Aminoalkyl Amines

An intriguing C?N transformation involving a catalyst‐free N‐alkylation/N′‐arylation process in a multicomponent reaction with secondary amines, cyclic tertiary amines and electron‐deficient aryl halides has been described. In this case, the N‐alkylation of secondary amines, utilizing cyclic tertiary amines as alkyl group sources, is enabled by a facile C?N cleavage. Such an operationally simple method could facilitate access to aromatic aminoalkyl amines, nitrogen‐containing bioactive molecules, in good to excellent yields.     

Rapid construction of multisubstituted olefin structures using vinylboronate ester platform leading to highly fluorescent materials

[reaction: see text] A catalytic one-pot triarylation on the C=C core of vinylboronate pinacol ester (1) produces extended pi-systems based on a multisubstituted olefin structure very rapidly. We established an efficient protocol for the Pd-catalyzed double C-H arylation of 1 with aryl halides, which was successfully integrated with C-B arylation with aryl halides (cross-coupling) in one pot. By using this method, several highly fluorescent materials with a wide range of color variations (blue to red) were discovered.     

(t-Bu)2PN=P(i-BuNCH2CH2)3N: new efficient ligand for palladium-catalyzed C-N couplings of aryl and heteroaryl bromides and chlorides and for vinyl bromides at room temperature

By employing Pd(OAc)2, Cs2CO3, or NaOH, and the new ligand (t-Bu)2PN=P(i-BuNCH2CH2)3N (3a), an electronically diverse array of aryl bromides and chlorides possessing base-sensitive substituents (nitro, ester, and keto) provide coupling products with bulky aryl amines in good to excellent yields. Aryl halides possessing other functional groups including cyano, amino, trifluoromethyl, and phenol, coupled with equal ease, producing highly functionalized amines in good to excellent yields. Moreover, an aryl chloro group can be preserved in the presence of a bromo substituent under our reaction conditions. BOC-protected amines also participated efficiently. Heterocyclic bromides and chlorides underwent clean couplings with amines in excellent yields. An important strength of our protocol is the use of lower palladium loadings than those reported earlier, without compromising yields. The air-stable palladium complex (eta3-cinnamyl)PdCl.(3a) (5) was also employed successfully in C-N coupling reactions while the crotyl analogue was less efficacious. The 3a/Pd(OAc)2 catalyst system promotes, for the first time, efficient coupling of vinyl bromides with a variety of amines to produce imines and enamines at room temperature.     

A facile protocol for N-Cbz protection of amines in PEG-600

正An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described.The reaction of amines with benzyl chloroformate(Cbz-Cl) in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent yields.The method is applicable to the N-Cbz protection of aliphatic(acyclic and cyclic) and aromatic amines.     

Room-Temperature Arylation of Thiols: Breakthrough with Aryl Chlorides

The formation of aryl C−S bonds is an important chemical transformation because aryl sulfides are valuable building blocks for the synthesis of biologically and pharmaceutically active molecules and organic materials. Aryl sulfides have traditionally been synthesized through the transition-metal-catalyzed cross-coupling of aryl halides with thiols. However, the aryl halides used are usually bromides and iodides; readily available, low-cost aryl chlorides often not reactive enough. Furthermore, the deactivation of transition-metal catalysts by thiols has forced chemists to use high catalyst loadings, specially designed ligands, high temperatures, and/or strong bases, thus leading to high costs and the incompatibility of some functional groups. Herein, we describe a simple and efficient visible-light photoredox arylation of thiols with aryl halides at room temperature. More importantly, various aryl chlorides are also effective arylation reagents under the present conditions.     

Room‐Temperature Arylation of Thiols: Breakthrough with Aryl Chlorides

The formation of aryl C−S bonds is an important chemical transformation because aryl sulfides are valuable building blocks for the synthesis of biologically and pharmaceutically active molecules and organic materials. Aryl sulfides have traditionally been synthesized through the transition‐metal‐catalyzed cross‐coupling of aryl halides with thiols. However, the aryl halides used are usually bromides and iodides; readily available, low‐cost aryl chlorides often not reactive enough. Furthermore, the deactivation of transition‐metal catalysts by thiols has forced chemists to use high catalyst loadings, specially designed ligands, high temperatures, and/or strong bases, thus leading to high costs and the incompatibility of some functional groups. Herein, we describe a simple and efficient visible‐light photoredox arylation of thiols with aryl halides at room temperature. More importantly, various aryl chlorides are also effective arylation reagents under the present conditions.     

氨基二硫代甲酸酯类化合物的合成新方法

在无水磷酸钾存在下,伯胺、仲胺和哌嗪与二硫化碳和不同的卤代烃于室温反应,高收率的生成对应的氨基二硫代甲酸酯.胺和卤代烃中含有-CONR₂,-OH,-CO₂H,-NO₂,-CO₂R,-CH(OR)₂,-C=C-,-CH₂OR,呋喃环和糖环等对酸或碱敏感的基团不受影响.     

Tandem amine propargylation-Sonogashira reactions: new three-component coupling leading to functionalized substituted propargylic amines

Three-component coupling reactions of propargyl halides, amines, and organic halides in the presence of palladium-copper catalysis produced efficiently highly functionalized propargylic amines in good to excellent yields at room temperature. Extension to the synthesis of 2-(dialkylaminomethyl)benzo[b]furan or indole derivatives is described.     

Nickel-catalyzed sp2 C-H bonds arylation of N-aromatic heterocycles with Grignard reagents at room temperature

A novel protocol for nickel-catalyzed direct sp(2) C-H bond arylation of purines has been developed. This new reaction proceeded efficiently at room temperature using Grignard reagent as the coupling partner within 5 hours in good to high yields. This approach provides a new access to a variety of C8-arylpurines which are potentially of great importance in medicinal chemistry.     

Synthesis and characterization of MCM‐41‐Biurea‐Pd as a heterogeneous nanocatalyst and using its catalytic efficacy in C–C,C–N and C–O coupling reactions

MCM‐41‐Biurea‐Pd is introduced as a new, heterogeneous and reusable catalyst for C–C and C–heteroatom bond formation between various aryl halides, phenols and amines, in the presence of Ph₃SnCl (Stille reaction) in PEG‐400 as a green solvent at room temperature. The structure of the functionalized MCM‐41 was analysed using various techniques.     

钯等过渡金属催化的卤代芳烃和胺的偶联反应

综述了钯等过渡金属催化的卤代芳烃或芳基碘酸酯和胺的偶联反应以及催化这 一新反应的催化剂的发展和应用。用于该反应的配体由P（o-tolyl)3发展到BINAP 及二烷基芳基膦，基底物由溴代芳烃扩展到经济易得的氯化芳烃及碘酸酯和各种胺。     

Visible‐Light‐Mediated Selective Arylation of Cysteine in Batch and Flow

A mild visible‐light‐mediated strategy for cysteine arylation is presented. The method relies on the use of eosin Y as a metal‐free photocatalyst and aryldiazonium salts as arylating agents. The reaction can be significantly accelerated in a microflow reactor, whilst allowing the in situ formation of the required diazonium salts. The batch and flow protocol described herein can be applied to obtain a broad series of arylated cysteine derivatives and arylated cysteine‐containing dipeptides. Moreover, the method was applied to the chemoselective arylation of a model peptide in biocompatible reaction conditions (room temperature, phosphate‐buffered saline (PBS) buffer) within a short reaction time.     

Cross‐Coupling of Sodium Sulfinates with Aryl,Heteroaryl, and Vinyl Halides by Nickel/Photoredox Dual Catalysis

An efficient photoredox/nickel catalyzed sulfonylation reaction of aryl, heteroaryl, and vinyl halides has been achieved for the first time. This newly developed sulfonylation protocol provides a versatile method for the synthesis of diverse aromatic sulfones at room temperature and shows excellent functional group tolerance. The electrophilic coupling partners are not limited to aryl, heteroaryl, and vinyl bromides and iodides, but also includes less reactive aryl chlorides as suitable substrates for this transformation.     

Cross‐Coupling of Sodium Sulfinates with Aryl,Heteroaryl, and Vinyl Halides by Nickel/Photoredox Dual Catalysis

An efficient photoredox/nickel catalyzed sulfonylation reaction of aryl, heteroaryl, and vinyl halides has been achieved for the first time. This newly developed sulfonylation protocol provides a versatile method for the synthesis of diverse aromatic sulfones at room temperature and shows excellent functional group tolerance. The electrophilic coupling partners are not limited to aryl, heteroaryl, and vinyl bromides and iodides, but also includes less reactive aryl chlorides as suitable substrates for this transformation.     

Polymer-supported organotin reagents for regioselective halogenation of aromatic amines

[reaction: see text] Polymer-supported triorganotin halides were used in the halogenation reaction of aromatic amines. Treatment of aromatic amines with n-butyllithium and polymer-supported organotin halides gave the corresponding polymer-bound N-triorganostannylamines, which by treatment with bromine or iodine monochloride gave the para-halogenated aromatic amines with high yields and high selectivities. The polymer-supported organotin halides reagents regenerated during the course of the halogenation reaction can be reused without loss of efficiency. The presence of tin residues in halogenated aromatic amines was also investigated and evaluated at under 20 ppm after three runs.     

Facile reaction of thiols and amines with alkyl 4-hydroxy-2-alkynoates in water under neutral conditions and ultrasound irradiation

This Letter describes an alternative protocol for the Michael addition of thiols to 4-hydroxy-2-alkynoates. The reaction proceeds at room temperature in water under ultrasound irradiation. With amines instead of thiols a sequential conjugate addition/lactonization reaction leads to important 4-amino-furan-2-one derivatives.