2769-64-4Relevant articles and documents
Reaction of Amines with Haloalkanes. 5. Dissolution of Copper Activated by Sulfur in n-Butylamine-Carbon Tetrachloride Solutions
Parodi, George A.,Miller, John G.
, p. 2968 - 2972 (1980)
Earlier study has shown that oxygen causes the dissolution of copper metal in amine-haloalkane solutions.We have found that sulfur also activates copper metal for the dissolution process.A kinetic study has been made by using n-butylamine and CCl4 as reactants at 30 deg C.A mechanism involving an intermediate copper(I) sulfide film is proposed.
Reaction of the Metallacycle n)S>(1+) with Nucleophiles. X-Ray Crystal Structures of the Comlexes n)S>SO3CF3 and SC(FeLn)S>n = Fe(cp)(CO)2, cp = η-C5H5>
Busetto, Luigi,Zanotti, Valerio,Albano, Vincenzo G.,Braga, Dario,Monari, Magda
, p. 1067 - 1074 (1988)
Reactions of the metallacyclic cation n)S>(1+)n = Fe(cp)(CO)2, cp = η-C5H5> with nucleophilic agents have been investigated.The results indicate that the carbene carbon atom bonded to the endocyclic iron is the site of addition of all the nucleophiles examined.Primary amines NH2R (R = Me, C6H11, or n-Bu) form neutral isocyanide derivatives n> with opening of the FeC2S2 ring, whereas secondary amines such as NHR2 (R = Me or Et) or HN(CH2)nCH2 (n = 3 or 4) produce stable cationic cyclic aminothiocarbenes.The structure of one of these, n)S>SO3CF3, has been determined by X-ray diffraction a = 11.570(2), b = 12.242(2), c = 10.552(2) Angstroem, α = 104.60(2), β = 87.51(1), γ = 117.24(2) deg, Z = 2, and space group P1>.The cation contains the five-membered planar ring FeSCSC with the Fe(cp)(CO)2 and NC5H10 groups bonded to the carbon atoms.The C(carbene)-N interaction exhibits strong double-bond character , typical for an iminium cation.Methanethiol, Li(BHEt3), and KCN yield neutral n)S> (X = SMe, H, or CN).In the hydride addition an isomeric mixture has been ascertained by i.r. and n.m.r. spectra, whereas the cyanide ion adds steroselectively at the prochiral carbene centre to form only one diastereoisomer whose steric nature has been determined by X-ray diffraction a = 6.894(2), b = 10.057(1), c = 14.520(2) Angstroem, α = 96.00(2), β = 96.17(1), γ = 106.31(1) deg, Z = 2, and space group P1>.In this derivative the FeSCSC ring undergoes substantial changes because the iron-bonded carbon atom becomes four-co-ordinate with loss of its carbenic character and significant out-of-plane displacement.A comparative analysis of the relevant geometric features of all the members of this family is reported.Propane-1,3-dithiol produces the neutral spirocyclic SC(FeLn)S> which shows equivalence of the two diastereotopic SCH2 carbons in the high-temperature 13C n.m.r. spectrum and splitting of ν(CO) in the i.r. spectrum.These spectroscopic features are discussed and interpreted.
Isocyanide 2.0
Ahmadian-Moghaddam, Maryam,D?mling, Alexander,Patil, Pravin
supporting information, p. 6902 - 6911 (2020/11/09)
The isocyanide functionality due to its dichotomy between carbenoid and triple bond characters, with a nucleophilic and electrophilic terminal carbon, exhibits unusual reactivity in organic chemistry exemplified for example in the Ugi reaction. Unfortunately, the over proportional use of only a few isocyanides hampers novel discoveries about the fascinating reactivity of this functional group. The synthesis of a broad range of isocyanides with multiple functional groups is lengthy, inefficient, and exposes the chemist to hazardous fumes. Here we present an innovative isocyanide synthesis overcoming these problems by avoiding the aqueous workup which we exemplify by parallel synthesis from a 0.2 mmol scale performed in 96-well microtiter plates up to a 0.5 mol multigram scale. The advantages of our methodology include an increased synthesis speed, very mild conditions giving access to hitherto unknown or highly reactive classes of isocyanides, rapid access to large numbers of functionalized isocyanides, increased yields, high purity, proven scalability over 5 orders of magnitude, increased safety and less reaction waste resulting in a highly reduced environmental footprint. For example, the hitherto believed to be unstable 2-isocyanopyrimidine, 2-acylphenylisocyanides and even o-isocyanobenzaldehyde could be accessed on a preparative scale and their chemistry was explored. Our new isocyanide synthesis will enable easy access to uncharted isocyanide space and will result in many discoveries about the unusual reactivity of this functional group. This journal is
Tandem reaction strategy of the Passerini/Wittig reaction based on the in situ capture of isocyanides: One-pot synthesis of heterocycles
Liu, Ming-Guo,Liu, Na,Xu, Wen-Heng,Wang, Long
, p. 2748 - 2754 (2019/04/04)
This paper reports the tandem reaction strategy of the Passerini/Wittig reaction based on the in situ capture of isocyanides. According to this strategy, plenty of isocyanides have been synthesized, which is immediately used for the tandem reaction of Passerini/Wittig reaction in one pot. Compared to the previous work, this strategy avoids the separation, purification, and storage of isocyanides, which prominently solves the problems of isocyanide-based multicomponent reaction such as: (a) The environmentally unfriendly (strong foul odor), (a) the labile of Isocyanides, (c) high toxicity of isocyanides. In the meantime, in order to expand the application scope of our strategy, 1H-isochromenes and 3H-2-benzoxepin-1-ones have also been synthesized, which undergoes four-step transformations in one-pot. In addition, a relatively credible reaction mechanism has also been proposed, based on a series of control experiments. Furthermore, preliminary testing was performed on biological activity of some obtained compounds; These results showed that the synthesized compounds exhibited certain activity over P. digitatum and P. italicum. 2019 Elsevier Science. All rights reserved.
Odorless Isocyanide Chemistry: One-Pot Synthesis of Heterocycles via the Passerini and Postmodification Tandem Reaction Based on the in Situ Capture of Isocyanides
Liu, Na,Chao, Fei,Liu, Ming-Guo,Huang, Nian-Yu,Zou, Kun,Wang, Long
, p. 2366 - 2371 (2019/05/16)
This paper reports the tandem reaction strategy of the Passerini/Staudinger/aza-Wittig reaction based on the in situ capture of isocyanides. According to this strategy, isocyanides are synthesized in situ and immediately work as the substrate for the Passerini reaction and postmodification tandem reaction in one pot. In addition, two types of new compounds, 5-oxo-3,5-dihydrobenzo[e][1,4]oxazepines and 6-oxo-5,6-dihydro-2H-1,4-oxazines, were synthesized using the tandem reaction strategy that includes five-step transformations in one pot.
Synthesis and structure–activity relationship of α-keto amides as enterovirus 71 3C protease inhibitors
Zeng, Debin,Ma, Yuying,Zhang, Rui,Nie, Quandeng,Cui, Zhengjie,Wang, Yaxin,Shang, Luqing,Yin, Zheng
supporting information, p. 1762 - 1766 (2016/12/22)
α-Keto amide derivatives as enterovirus 71 (EV71) 3C protease (3Cpro) inhibitors have been synthesized and assayed for their biochemical and antiviral activities. structure–activity relationship (SAR) study indicated that small moieties were primarily tolerated at P1' and the introduction of para-fluoro benzyl at P2 notably improved the potency of inhibitor. Inhibitors 8v, 8w and 8x exhibited satisfactory activity (IC50= 1.32 ± 0.26 μM, 1.88 ± 0.35 μM and 1.52 ± 0.31 μM, respectively) and favorable CC50values (CC50> 100 μM). α-Keto amide may represent a good choice as a warhead for EV71 3Cproinhibitor.
Higher-order cyclopropenimine superbases: Direct neutral br?nsted base catalyzed michael reactions with α-aryl esters
Nacsa, Eric D.,Lambert, Tristan H.
supporting information, p. 10246 - 10253 (2015/09/01)
The synthesis and characterization of six new classes of higher-order superbases, including five that incorporate cyclopropenimine functionality, has been achieved. We propose a nomenclature that designates these as the CG2, GC2, PC3, PC1, C3, and GP2 classes of superbases. The pKBH+ values were measured to be between 29.0 and 35.6 in acetonitrile. Linear correlations of ten superbase basicities vs that of their substituents demonstrated the insulating effect of the cyclopropenimine core. The molecular structures of several of these materials were obtained by single-crystal X-ray analysis, revealing interesting aspects of conformational bias and noncovalent organization. The types of superbasic cores and substituents were each reliably shown to affect selectivity for deprotonation over alkylation. Higher-order cyclopropenimine and guanidine superbase stability to hydrolysis was found to correlate to basicity. Finally, a GC2 base was found to catalyze conjugate additions of α-aryl ester pronucleophiles, representing the first report of a neutral Br?nsted base to catalyze such reactions.
Regioselective one-pot three component synthesis of chiral 2-iminoselenazolines under sonication
Chang, Wong-Jin,Kulkarni, Manohar V.,Sun, Chung-Ming
, p. 97113 - 97120 (2015/12/01)
A one-pot multi component reaction of selenoureas, which are in situ generated from l-amino esters and isoselenocyanates, with α-bromoketone under ultrasonication. Selenourea and α-bromoketones formed 2-iminoselenazoles through a Hantzsch selenazole-type reaction. The steric effect of the α-substituted bromoketones on the rate of the tandem reaction was studied to understand the reaction mechanism by isolating the key reaction intermediate, 2-iminoselenol.
Multicomponent cascade cycloaddition involving tropone, allenoate, and isocyanide: A rapid access to a 7,6,5-fused tricyclic skeleton
Jia, Shuanglong,Su, Shikuan,Li, Chunju,Jia, Xueshun,Li, Jian
supporting information, p. 5604 - 5607 (2015/02/19)
Multicomponent cascade cycloaddition of tropone, allenoate, and isocyanide has been disclosed. This method allows for the rapid construction of a highly unusual tricyclic skeleton in an efficient manner. The proposed transformation proceeds through [8 + 2 + 1] cycloaddition, [1,5]-H shift, and cyclization followed by an alkoxy group migration process.
One-pot synthesis of 1-substituted-5-alkylselanyl-1H-tetrazoles from isoselenocyanates: Unexpected formation of N-alkyl-N-arylcyanamides and (Z)-Se-alkyl-N-cyano-N,N′-diarylisoselenoureas
Karabanovich, Galina,Roh, Jaroslav,Padělková, Zdeňka,Novák, Zdeněk,Vávrová, Kate?ina,Hrabálek, Alexandr
, p. 8798 - 8808 (2013/09/23)
1-Substituted-5-alkylsulfanyl-1H-tetrazoles are well known class of organic substances with various applications in medicinal chemistry or photographic industry. Their selenium analogues, 1-substituted-5-alkylselanyl-1H-tetrazoles are, however, much less explored because of the lack of suitable methods for their preparation. In this work we investigated the synthesis of 1-alkyl/aryl-5-alkylselanyl-1H-tetrazoles from synthetically available alkyl/arylisoselenocyanates. One-pot reactions of arylisoselenocyanates with sodium azide and alkylating agent led to the target 5-alkylselanyl-1-aryl-1H- tetrazoles but also to interesting side products, namely N-alkyl-N- arylcyanamides and (Z)-Se-alkyl-N-cyano-N,N′-diarylisoselenoureas. Nevertheless, when alkylisoselenocyanates were utilized as the substrates, the reactions led exclusively to the formation of 1-alkyl-5-alkylselanyl-1H- tetrazoles in good yields. This simple one-pot procedure brings new possibilities for the preparation of variously substituted selenium compounds. It also opens the way to further investigations of selenium isosteres of the widely utilized 5-thiotetrazole moiety in biomedical applications.
