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1.
Synthesis of N-tosylimines of arylaldehydes was carried out by the reaction of arylaldehydes and p-toluenesulfonamide in methylene chloride in the presence of trifluoroacetic anhydride as a dehydrating agent.  相似文献   

2.
A Pd2dba3/P(i-BuNCH2CH2)3N catalyzed one-pot synthesis of unsymmetrically substituted trans-4-N,N-diarylaminostilbenes and both symmetrically and unsymmetrically substituted N,N-diarylaminostyrene derivatives is reported. The procedure involves two or more palladium catalyzed sequential coupling reactions (an amination and an inter-molecular Heck reaction) in one-pot using the same catalyst system with two different aryl halides, including aryl chlorides and hetero aryl halides as the coupling partners.  相似文献   

3.
Ying-Wen Guo  Hong-Bin Li 《Tetrahedron》2006,62(25):5875-5882
Reactions of diethyl acetylenedicarboxylate with salicyl N-tosylimines or salicylaldehydes proceeded smoothly in the presence of DABCO or dimethylphenylphosphine under mild conditions to give the corresponding chromenes in excellent yields.  相似文献   

4.
《Tetrahedron letters》2004,45(38):7061-7064
End-capped (N,N-dimethylaminophenyl) and 2′-thienylethynyl 2,5-thiophene oligomer structures were synthesized by heterocoupling between the terminal acetylenes such as: p-(N,N-dimethylaminophenyl)ethyne (3) [or 1-(p-(N,N-dimethylaminophenyl)-2-p-(ethynylphenyl)ethyne, 4]; p-(β-ethenyl-2′-thienyl)phenylethyne (E-9) [or p-(β-ethynyl-2′-thienyl)phenylethyne, 11], and 2,5-diiodothiophene, catalyzed by the Cl2Pd(PPh3)2/CuI system, in good to excellent yields. The 2,5-di[(3′,5′-di(trimethylsilylethynyl)phenyl]x-1-ethynyl]thiophene oligomers were prepared by heterocoupling between 3′,5′-di[(trimethylsilylethynyl)phenyl]x-1-ethyne (n = 0-2) terminal acetylenes and 2,5-diiodothiophene, in excellent yields. The terminal acetylenes were efficiently prepared by a specific protection-deprotection methodology. All the ethynylphenyl compounds obtained show fluorescence radiation emission, with a bathochromic shift of the wavelength that increases with the chain conjugation.  相似文献   

5.
Et3N-catalyzed reactions of salicyl N-tosylimines or salicylaldehydes with methyl 2-perfluoroalkynoates proceed smoothly at room temperature in dichloromethane (DCM) or dimethyl sulfoxide (DMSO) to give the corresponding fluorinated chromenes in good to excellent yields with high regioselectivity.  相似文献   

6.
Regioselective synthesis of 1-arylnaphthalene derivatives was carried out from N-tosylaziridines, which was made from the reaction of N-tosylimines and cinnamyl bromides by using the sulfur ylide chemistry.  相似文献   

7.
Facile N-tert-butoxycarbonylation of amines is described by the treatment of various primary, secondary, benzylic and aryl amines with di-tert-butyl dicarbonate in the presence of catalytic amounts of La(NO3)3·6H2O under solvent-free conditions at room temperature to afford N-tert-butylcarbamates in excellent yields.  相似文献   

8.
A new family of the end-capped 5-(N,N-dimethylamino)naphthylethynyl chains were synthesized, as terminal acetylenes or poly(yne) structures, by heterocoupling between 5-iodo-N,N-dimethylnaphthalen-1-amine and 2-methyl-3-butyn-2-ol or 4-(5-iodo-1-naphthyl)-2-methyl-3-butyn-2-ol, catalyzed by the palladium-copper system. Catalytic homocoupling of the terminal acetylenes, affords to 1,4-dinaphthyl-1,3-butadiyne nanostructures. X-ray diffraction analysis of 1,4-di(α-naphthyl)-1,3-butadiyne shows that the naphthalene rings are in the anti configuration along the acetylene axis. All the conjugated compounds show an important fluorescent emission radiation.  相似文献   

9.
Thermal ring-opening reaction of N-(R-dinitromethyl)-5-nitrotetrazoles (R=NO2, F, Cl) yielded highly reactive N-(R-dinitromethyl)-nitrilimine intermediates under mild conditions. These species underwent facile and regiospecific reaction with nitriles and acetylenes to afford the corresponding nitrotriazoles and nitropyrazoles in 50-90% yields. Treatment of N-(chlorodinitromethyl)-5-nitrotetrazole with the excess of azide led to a unique compound with the molecular formula C2N14. Based on the analytical data, it was assigned a structure of diazidomethylenecarbonohydrazonic diazide.  相似文献   

10.
An expeditious synthetic method of 3-arylidenelactams was developed starting from N-tosylaziridines, which were made from the reaction of N-tosylimines and cinnamyl bromides by using the sulfur ylide chemistry. The regioselective ring-opening reaction of N-tosylaziridines with anilines, as external nucleophiles, and the following lactamization afforded 3-arylidenelactams. In the absence of external nucleophiles, intramolecular lactonization occurred to afford 3-arylidenelactones.  相似文献   

11.
A new water soluble palladium(II) complex (2) derived from N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine (edteH4) (1) was synthesized in high yield and characterized by 1H, 13C, HMQC and COSY NMR spectroscopy. X-ray diffraction studies on a single crystal of 2 confirmed the cis square planar geometry; the edteH4 ligand (1) is κ2 (N,N)-coordinated with four pendant CH2CH2OH groups. This new complex [PdCl2(edteH4)] (2) and the previously synthesized triethanolamine complex [Pd(OCH2CH2N(CH2CH2OH)2)2] (3) were tested as catalysts for the Suzuki/Miyaura cross-coupling reaction of various aryl bromides with phenylboronic acid in water. Electronically activated aryl bromides, such as 4-bromoacetophenone and 4-bromobenzaldehyde undergo the cross-coupling with extremely high turnover numbers (TON) of up to 1,00,000 without organic solvent.  相似文献   

12.
We present a new and concise method for the preparation of asymmetrical N,N′-disubstituted guanidines starting from thiourea via the reaction of N-Boc-protected N′-alkyl/aryl substituted thioureas with an amine in the presence of mercury(II) chloride and triethylamine.  相似文献   

13.
Aihua Zhou 《Tetrahedron》2006,62(17):4093-4102
2-Alkyloxazolines and 2-alkylthiazolines react with 2-halobenzoyl chlorides to form N-(2-halobenzoyl)-cyclic ketene-N,O-acetals and N-(2-halobenzoyl)-cyclic ketene-N,S-acetals in excellent yields, respectively. These ketene acetals readily undergo stereocontrolled aryl radical cyclizations to afford the central six-membered rings of substituted-2,3,10,10α-tetrahydrooxazolo[3,2-b]isoquinolin-5-ones and their 2,3,10,10α-tetrahydrothiazolo[3,2-b]isoquinolin-5-one analogs. The tertiary N,O- and N,S-radicals formed upon aryl radical reaction at the ketene-N,X(X=O, S)-acetal double bond appear to have reasonable stability. The stereoselectivity in hydrogen abstractions by these intermediate radicals from both Bu3SnH and (Me3Si)3SiH was investigated. The N,S-heterocyclic fused ring products may have potential medical value.  相似文献   

14.
E.A. Jaseer 《Tetrahedron letters》2010,51(38):5009-5012
A wide range of 2-aryl or 2-alkyl-substituted benzothiazoles are synthesized through intramolecular C(aryl)-S bond forming-cyclization using copper(II)-BINAM-catalyzed coupling of less reactive N-(2-chlorophenyl)benzo or alkylthioamide under mild reaction conditions (82 °C).  相似文献   

15.
Chiral N,N-diaryl C2-symmetric diamines and N-aryl,N′-formyl-trans-(1R,2R)-diaminocyclohexane are readily accessed by copper catalyzed N,N-diarylation and N-aryl,N′-formylation of trans-(1R,2R)-diaminocyclohexane with aryl bromides. N,N′-diarylation using (R)-1,1′-binaphthyl-2,2′-diamine and iodobenzene gave the corresponding (R)-N,N-diphenyl-1,1′-binaphthyl-2,2′-diamine derivative in 83% yield.  相似文献   

16.
Yoshikatsu Ito 《Tetrahedron》2007,63(15):3108-3114
Photocarboxylation of 1,1-diphenylethylene with N,N,N′,N′-tetramethylbenzidine (TMB) in MeCN under bubbling of CO2 proceeded with high catalytic efficiency, giving 3,3-diphenylacrylic acid (DPA) and 3-hydroxy-3,3-diphenylpropionic acid (20). The turnover number (TON=(DPA+20)/TMB) reached 17. Similarly, 1-phenyl-1-cyclohexene yielded cis-2-acetamido-2-phenylcyclohexanecarboxylic acid with TON 5.9. As compared with related N,N-dimethylaniline derivatives, TMB is more resistant to photodecomposition, has the much larger absorbance in the S0→S1 transition, and has the lower quenching efficiency by CO2. Probably these factors are partly responsible for the high TON observed for TMB.  相似文献   

17.
Ming-Juan Qi 《Tetrahedron》2007,63(42):10415-10424
Reactions of salicyl N-tosylimines with methyl vinyl ketone, ethyl vinyl ketone or phenyl vinyl ketone proceeded smoothly under mild conditions to give the corresponding chromanes or aza-Baylis-Hillman adducts in moderate to excellent yields in the presence of phosphine or nitrogen Lewis base.  相似文献   

18.
A transition-metal-free method for the synthesis of indolines has been developed. In the presence of K2CO3, the cyclization reaction of N-(ortho-chloromethyl)aryl amides and iodonium ylides proceeded smoothly at room temperature in moderate to good yields.  相似文献   

19.
A novel and convenient protocol for the synthesis of N-cyanobenzamides starting from readily available aryl halides and cyanamide via palladium-catalyzed aminocarbonylation has been developed. The protocol utilizes Mo(CO)6 as the CO source or CO(gas) and affords the desired N-cyanobenzamides in moderate to good yields.  相似文献   

20.
Siddappa A. Patil 《Tetrahedron》2009,65(15):2889-1412
N,N,O-Tridentate ligands 1-9 were prepared from the condensation of amines with nine aromatic aldehydes or ketones. These ligands are thermally stable and neither air- nor moisture-sensitive. Combination of either 2-methoxy-6-[(pyridine-2-ylmethylimino)-methyl]-phenol, 1 or 2-(benzothiazol-2-yl-hydrazonomethyl)-4,6-di-tert-butyl-phenol, 6 with Pd(OAc)2 furnished an excellent catalyst precursor for the Suzuki-Miyaura cross-coupling of various aryl bromides with arylboronic acids. The effects of varying solvents, bases, and ligand/palladium ratios on the performance of the coupling reaction were investigated. The molecular structures of both free ligand 1 and its palladium acetate complex 10 were determined by single-crystal X-ray diffraction methods. The DFT studies revealed that the catalytic performance of palladium complexes involving this type of a ligand may differ greatly upon a small variation in its structure.  相似文献   

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