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1.
A High Yielding, One-Pot, Triton-B Catalyzed Synthesis of Dithiocarbamates Using Alcoholic Tosylates
Summary. A novel process for the one-step chemoselective conversion of alcoholic tosylates into dithiocarbamates as protected amines
was developed using benzyltrimethylammoniumhydroxide (Triton-B) in presence of carbon disulfide. Thus, dithiocarbamates of
different amines were prepared in very good to excellent yields. This protocol is mild, chemoselective, and efficient compared
to other reported methods.
Present address: Institute of Organic and Biomolecular Chemistry, Georg-August University, D-37077, G?ttingen, Germany 相似文献
2.
A novel process for the one-step chemoselective conversion of alkyl halides into dithiocarbamates as protected amines was
developed using benzyltrimethylammonium hydroxide (Triton-B) in presence of carbon disulfide. Thus, dithiocarbamates of different
amines were prepared in very good to excellent yields. This protocol is mild, chemoselective, and efficient compared to other
methods. 相似文献
3.
A Mitsunobu-based protocol has been developed for the synthesis of dithiocarbamates from the corresponding alcohols using carbon disulfide and amines in good to excellent yields. This protocol is mild, chemoselective and efficient compared to other reported methods. 相似文献
4.
Summary. A novel process for the one-step chemoselective conversion of alkyl halides into carbamates as protected amines was developed
using benzyltrimethylammonium hydroxide (Triton-B) in presence of gaseous carbon dioxide. Thus, carbamate esters of different
amines were prepared in very good to excellent yields.
Present address: Institute of Organic and Biomolecular Chemistry, George–August University, 37077, G?ttingen, Germany 相似文献
5.
Devdutt Chaturvedi Nisha Mishra Virendra Mishra 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):57-60
Summary. A novel Mitsunobu-based protocol was developed for the synthesis of carbamates from the corresponding alcohols using carbon dioxide and amines
in good to excellent yields. This protocol is mild, chemoselective, and efficient compared to other reported methods. 相似文献
6.
Meriem Toumi Noureddine Raouafi Khaled Boujlel Issa Tapsoba Jean-Paul Picard Michel Bordeau 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2477-2490
Electrogenerated cyanomethyl anion promotes the reaction between primary or secondary amines, carbon disulfide, and alkyl or benzyl halide. Secondary amines are converted to alkyl or benzyl dithiocarbamates, whereas primary amines give N-substituted alkyl or benzyl 3-amino-2-cyanodithiocrotonates. The mechanisms are discussed. 相似文献
7.
Ghasem Rezanejade Bardajee Hamid Samareh Afsari Seyediraj Sadraei Seyedehmaryamdokht Taimoory 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):871-878
Abstract An efficient, versatile, and environmentally benign method for the synthesis of dithiocarbamates under solvent-free conditions is reported. The Michael addition of electron-deficient alkenes with alkyl or aryl amines and CS2 in the presence of OH?/silica in a one-pot three-component reaction protocol gave the corresponding dithiocarbamates in good to excellent yields. This method is suitable for a wide range of amines and a variety of Michael acceptors in solvent-free conditions. The results of the present work show the desired products in excellent yields. 相似文献
8.
Heshmatollah Alinezhad Mahmoud Tajbakhsh Roja Enayati Ahangar 《Monatshefte für Chemie / Chemical Monthly》2008,139(1):21-25
Summary. A chemoselective, fast, efficient, and high yielding method for the preparation of amines by reductive amination of aldehydes
and ketones using sodium borohydride in the presence of silica phosphoric acid in THF and under solvent-free conditions at room temperature is described. 相似文献
9.
Primary and secondary aliphatic amines (ca. 0.2–6 μg ml?1) determined at 250 and 280 nm, respectively, after in situ derivatization to dithiocarbamates in a carbon disulphide/ aqueous sodium hydroxide two-phase system. Alcohols, aromatic and tertiary amines do not interfere. 相似文献
10.
Vinod K. Tiwari Archana Singh Hakkim A. Hussain Bhuwan B. Mishra Vyasji Tripathi 《Monatshefte für Chemie / Chemical Monthly》2007,138(7):653-658
Summary. A convenient and high yielding method for the synthesis of diverse dithiocarbamates having various substituents including
alkyl, aryl, heteroaryl, and alkylaryl at the thiol chain or at the amine chain or at both thiol and amine chains were developed
by the one-pot reaction of mercaptans, amines, and bis(benzotriazolyl)methanethione in presence of amidine base under mild
reaction conditions. 相似文献
11.
Summary. A novel process for the one-step chemoselective conversion of a variety of alcoholic tosylates into carbamates serving as
protected amines was developed using benzyltrimethylammonium hydroxide (Triton-B) in the presence of gaseous carbon dioxide.
Thus carbamate esters of different amines were prepared in very good to excellent yields.
Present address: Institute of Organic and Biomolecular Chemistry, Georg-August University, D-37077, G?ttingen, Germany 相似文献
12.
Luu Van Boi 《Russian Chemical Bulletin》2000,49(2):335-343
Thiocarbamoylation of aliphatic amines with tetramethylthiuram disulfide (TMTD) was studied. The reactions were established
to proceed according to a two-stage mechanism. In the first stage,S-(thiocarbamoyl)thiohydroxylamines and dimethyl dithiocarbamates are formed. The latter exist in equilibrium with dimethyldithiocarbamic
acid, which can undergo decomposition to give dimethylamine and carbon disulfide. In the second stage, several competitive
transformations of these intermediates into the final products occur,viz., (1) the reactions of CS2 with primary amines on heating (70–110 °C) yield mixed and symmetrical thioureas and the reactions of CS2 with secondary amines give symmetrical dithiocarbamates, and (2) insertion of CS2 intoS-(thiocarbamoyl)thiohydroxylamines affords thiuram disulfides. Thiuram disulfides formed from primary amines decompose to
give isothiocyanates, which are converted into thioureas by condensation with amines, whereas thiuram disulfides which are
obtained in the reactions with secondary amines and which cannot form thioureas react with amines analogously to TMTD.
For Part 4, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 334–342, February, 2000. 相似文献
13.
An efficient method for synthesis of 2H-pyran-3,4-dicarboxylates using the three-component reaction of dithiocarbamates, dialkyl acetylenedicarboxylates, and isocyanides in solvent-free conditions is described. In these reactions, synthesis of dithiocarbamates is possibly based on the one-pot reaction of secondary amines, CS2, and alkyl halides in solvent-free conditions without using a catalyst. The mild reaction conditions and high yields of the reaction exhibit the good synthetic advantage of these methods. 相似文献
14.
Mahagundappa Maddani 《Tetrahedron letters》2007,48(40):7151-7154
A convenient method for the synthesis of substituted thioureas by the reaction of primary amines with molybdenum dialkyl dithiocarbamates has been developed. Primary amines on reaction with 0.5 equiv of molybdenum xanthate produce the corresponding thioureas in moderate to good yields in short times. Similar reactions with propargylamine or 2-aminoethanol produce cyclic thiaoxazolidine and oxazolidine derivatives, respectively. 相似文献
15.
Shuhei Uesugi Zhao Li Dr. Ryo Yazaki Prof. Dr. Takashi Ohshima 《Angewandte Chemie (International ed. in English)》2014,53(6):1611-1615
A highly chemoselective conjugate addition of alcohols in the presence of amines is described. The cooperative nature of the catalyst enabled chemoselective activation of alcohols over amines, allowing the conjugate addition to soft Lewis basic α,β‐unsaturated nitriles. Divergent transformation of the nitrile functionality highlights the utility of the present catalysis. 相似文献
16.
Structural diversity is possible in direct access to functional dithiocarbamates based on a highly efficient and simple one-pot reaction of CS2, amines, and alkyl halides in nearly quantitative yields in water. 相似文献
17.
A simple, facile, and chemoselective N-benzyloxycarbonylation of amines using silica-sulfuric acid that proceeds under solvent-free conditions at room temperature has been achieved. These reactions are applicable to a wide variety of primary (aliphatic and cyclic) secondary amines, amino alcohols, and heterocyclic amines. 相似文献
18.
19.
Ahmed Kamal Dr. Nagula Markandeya Nagula Shankaraiah Dr. C. Ratna Reddy S. Prabhakar C. Sanjeeva Reddy Prof. Marcos N. Eberlin Prof. Leonardo Silva Santos Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(29):7215-7224
Aluminium and gadolinium triflates catalyze the chemoselective reduction of aromatic azides to the corresponding amines in combination with sodium iodide. This mild chemoselective method has been applied to the synthesis of various aryl amines, C2‐azido‐substituted pyrrolo[2,1‐c][1,4]benzodiazepines, and fused[2,1‐b]quinazolinones by an intramolecular azido reduction tandem cyclization reaction. Interestingly, this methodology selectively reduces aryl azides with enhanced yields and proceeds in shorter reaction times than previous strategies. The mechanistic aspects have been investigated and the intermediates associated with this selective transformation have been intercepted and characterized by online monitoring of the reaction by ESI‐MS. 相似文献
20.
Srivastava A 《Talanta》1982,29(1):31-35
Iodoso derivatives, e.g., m- and p-chlorophenyl, m- and p-methylphenyl and p-nitrophenyl-iodosoacetates and o-diacetoxyiodobenzoate, have been thoroughly investigated as oxidants and are proposed as analytical reagents for the determination of thiols, thioureas, isothiocyanates, organic sulphides, disulphides, xanthates, dithiocarbamates, amines and alcohols in aqueous and non-aqueous (acetic acid, acetonitrile, dimethylformamide) media. The error of the determination of thiols is 0.2% thioureas 0.5%, organic sulphides and disulphides 0.4%, isothiocyanates 0.4%, dithiocarbamates 0.4%, and xanthates 0.5%. All the methods are precise to 0.2-0.5%. It is also shown that the properties of the o-derivatives differ markedly from those of the m- and p-derivatives. The o-derivatives contain a 1-substituted 1,2-benzoiodoxilin-3-one ring system. The stability of this system is apparently associated with the size of the five-membered ring; other compounds in which iodine is apparently part of larger rings are less stable. o-Diacetoxyiodobenzoate appears to be the best analytical reagent of the iodoso series. The m- and p-iodosobenzoates are found unsuitable for quantitative oxidation of cysteine. 相似文献