- Conversion of Amides and Lactams to Thioamides and Thiolactams Using Hexamethyldisilathiane
-
Amides and lactams were converted to their corresponding thioamides and thiolactams employing a new protocol using hexamethyldisilathiane (TMS2S).Oxophilic promoters were employed to generate Vilsmeier-type intermediates, the most efficient reagents being phosphorus oxychloride, triphosgene, and oxalyl chloride.Thionation of intermediate chloro iminium ions was accomplished in situ with TMS2S.Yields were good to excellent for secondary and tertiary amides and lactams while yields for primary systems were poor.
- Smith, D. C.,Lee, S. W.,Fuchs, P. L.
-
-
Read Online
- A Facile Conversion of Amides and Lactams to Thioamides and Thiolactams using Tetrathiomolybdate
-
Chloro iminium salts generated in situ from amides and lactams using (COCl)2 or POCl3 reacted very readily with the new sulfur transfer reagent, benzyltriethylammonium tetrathiomolybdate to afford the corresponding thioamides and thiolactams in excellent yields under mild reaction conditions.
- Ilankumaran, Palanichamy,Ramesha, A. R.,Chandrasekaran, Srinivasan
-
-
Read Online
- Modification of organic compounds with Lawesson's reagent
-
Application in organic synthesis of Lawesson's reagent, 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide, provides a possibility to replace an oxygen atom for a sulfur atom in the carbonyl group of ketones, esters, amides, in ether group, and also either to induce a rearrangement of the initial structure of organic compounds with or without inclusion of sulfur atoms or to lead to the formation of various types of organophosphorus compounds. The formed organosulfur compounds exhibit a wide range of biological action.
- Kayukova,Praliyev,Gut'Yar,Baitursynova
-
p. 148 - 160
(2015/04/14)
-
- A new application of rhodanine as a green sulfur transferring agent for a clean functional group interconversion of amide to thioamide using reusable MCM-41 mesoporous silica
-
A novel thionation protocol for amide compounds, with the system rhodanine/secondary amine has been discovered. Clean and efficient synthesis of a variety of thioamides can be achieved through this simple and convenient method using MCM-41 mesoporous silica as an acid catalyst. For this purpose we have synthesized MCM-41 silica and characterized by using an array of sophisticated analytical techniques like BET, HR TEM, EDX, XRD, 29Si MAS NMR and FTIR. This reaction is therefore a very neat example of a functional group interconversion.
- Ray, Suman,Bhaumik, Asim,Dutta, Arghya,Butcher, Ray J.,Mukhopadhyay, Chhanda
-
p. 2164 - 2170
(2013/05/08)
-
- Ruthenium catalyzed synthesis of enaminones
-
The Grubbs first-generation catalyst has been found to be an effective catalyst for the synthesis of enaminones by coupling thioamides with α-diazodicarbonyl compounds. The reaction is successful in converting primary, secondary, and tertiary thioamides into their corresponding enaminones. The reaction is also suitable for the synthesis of chiral enaminones.
- Koduri, Naga Durgarao,Scott, Halee,Hileman, Bethany,Cox, Justin D.,Coffin, Michael,Glicksberg, Lindsay,Hussaini, Syed R.
-
supporting information; experimental part
p. 440 - 443
(2012/03/10)
-
- Thionation of amides using a solid-supported P2S5 reagent under microwave irradiation
-
In this Letter, we describe an improved method for the thionation of amides. Using a solid-supported P2S5 reagent, heating under microwave irradiation furnished thioamides in good to excellent yields, with a significantly reduced reaction time compared with that achieved under conventional heating. Furthermore, a change of solvent from that described in the literature enabled a simplified work-up and purification of the products.
- Lagiakos, Helen Rachel,Walker, Ashley,Aguilar, Marie-Isabel,Perlmutter, Patrick
-
experimental part
p. 5131 - 5132
(2011/10/12)
-
- Reaction of optically active oxiranes with thiofenchone and 1-methylpyrrolidine-2-thione: Formation of 1,3-oxathiolanes and thiiranes
-
The SnCl4-catalyzed reaction of (-)-thiofenchone (=1,3,3-trimethylbicyclo[2.2.1]heptane-2-thione; 10) with (R)-2-phenyloxirane ((R)-11) in anhydrous CH2Cl2 at -60° led to two spirocyclic, stereoisomeric 4-phenyl-1,3-oxathiolanes 12 and 13 via a regioselective ring enlargement, in accordance with previously reported reactions of oxiranes with thioketones (Scheme 3). The structure and configuration of the major isomer 12 were determined by X-ray crystallography. On the other hand, the reaction of 1-methylpyrrolidine-2-thione (14a) with (R)-11 yielded stereoselectively (S)-2-phenylthiirane ((S)-15) in 56% yield and 87-93% ee, together with 1-methylpyrrolidin-2-one (14b). This transformation occurs via an SN2-type attack of the S-atom at C(2) of the aryl-substituted oxirane and, therefore, with inversion of the configuration (Scheme 4). The analogous reaction of 14a with (R)-2-{[(triphenylmethyl)oxy] methyl}oxirane ((R)-16b) led to the corresponding (R)-configured thiirane (R)-17b (Scheme 5); its structure and configuration were also determined by X-ray crystallography. A mechanism via initial ring opening by attack at C(3) of the alkyl-substituted oxirane, with retention of the configuration, and subsequent decomposition of the formed 1,3-oxathiolane with inversion of the configuration is proposed (Scheme 5). Copyright
- Fu, Changchun,Linden, Anthony,Heimgartner, Heinz
-
experimental part
p. 773 - 784
(2011/06/27)
-
- Expeditious microwave-assisted thionation with the system PSCl 3/H2O/Et3N under solvent-free condition
-
(Chemical Equation Presented) A novel thionation protocol for carbonyl compounds, with the system PSCl3/H2O/Et3N has been discovered. Clean, rapid, and efficient synthesis of a variety of thiocarbonyl compounds such as thioamides, thiolactams, thioketones, thioxanthones, and thioacridone can be achieved through this simple and convenient method under solventless condition with microwave irradiation.
- Pathak, Uma,Pandey, Lokesh Kumar,Tank, Rekha
-
p. 2890 - 2893
(2008/09/19)
-
- Synthesis and application of a fluorous Lawesson's reagent: Convenient chromatography-free product purification
-
A fluorous analogue of Lawesson's reagent for thionation of carbonyl compounds has been developed and its use demonstrated on a series of amides, esters, and ketones. The separation of the Lawesson's reagent-derived byproducts can be achieved by a simple fluorous solid-phase extraction.
- Kaleta, Zoltan,Tarkanyi, Gabor,Goemoery, Agnes,Kalman, Ferenc,Nagy, Tamas,Soos, Tibor
-
p. 1093 - 1095
(2007/10/03)
-
- Synthesis of ω-aminodithioesters
-
ω-Aminodithioester derivatives were obtained from thionolactams by reaction with an alkyl triflate followed by thiolysis with hydrogen sulfide. The presence of an electron-withdrawing group was required on the N1 position (p-nitrophenyl or benzoyl) to favor the ring opening of γ-, δ- and ε-thionolactams. In the case of β-thionolactam, activation was provided by a CF2 motif in C3 position. Georg Thieme Verlag Stuttgart.
- Lacroix, Simon,Rixhon, Vinciane,Marchand-Brynaert, Jacqueline
-
p. 2327 - 2334
(2008/02/03)
-
- Coupling-isomerization - N,S-ketene acetal-addition sequences - A three-component approach to highly fluorescent pyrrolo[2,3-b]pyridines, [1,8]naphthyridines, and pyrido[2,3-b]azepines
-
Annelated 2-amino pyridines such as pyrrolo[2,3-b]pyridines, [1,8]naphthyridines, and pyrido[2,3-b]-azepines can be synthesized in moderate to good yields in a consecutive one-pot three-component process by a coupling-isomerization-enamine-addition-cycloc
- Schramm, Oana G.,Dediu, Nee,Oeser, Thomas,Mueller, Thomas J. J.
-
p. 3494 - 3500
(2007/10/03)
-
- Preparation and reductive transformations of vinylogous sulfonamides (β-sulfonyl enamines), and application to the synthesis of indolizidines
-
Condensation between the methiodide salts of 1-alkylpyrrolidine-2-thiones and ethyl [(4-methylphenyl)sulfonyl]acetate or 1-[(4-methylphenyl)sulfonyl]propan-2-one afforded several 2-{[(4-methylphenyl)sulfonyl]methylene}pyrrolidines in good yield. These β-sulfonyl enamines are sufficiently nucleophilic for cyclisation with internal electrophiles to give sulfone-substituted indolizines, potentially useful scaffolds for alkaloid synthesis. The carbon-carbon double bond in vinylogous sulfonamides was reduced stereoselectively either by catalytic hydrogenation or by treatment with sodium borohydride to yield β-sulfonyl amines. The sulfone group in β-acyl-β-sulfonyl enamines could be removed by hydrogenolysis with sodium amalgam in THF-methanol to give enaminones.
- Michael, Joseph P.,De Koning, Charles R.,Malefetse, Tshepo J.,Yillah, Ibrahim
-
p. 3510 - 3517
(2007/10/03)
-
- Transformation of Alkyl N-(Vinyloxy)benzimidates to Alkyloxazoles. Mechanism and Extension
-
Transformation of alkyl N-(vinyloxy)benzimidates to alkyloxazoles proceeds through the intermediates: a charge-separated 1,2-oxazetidine derivative and then 1-hydroxy-2-imino>maleic acid diester, while their photochemical transformation takes place via a concerted sigmatropic shift.As the extension of this reaction, the preparation of the precursor proposed for virginiamycin M2 synthesis and the reaction of N-analogs of alkyl N-(vinyloxy)benzimidates are described.
- Yokoyama, Masataka,Menjo, Yasuhiro,Ubukata, Makoto,Irie, Masakazu,Watanabe, Mikari,Togo, Hideo
-
p. 2219 - 2226
(2007/10/02)
-
- Sulfidation of Selected Carboxylic and Carbonic Acid Amides with the (9-BBN)2S-Reagent
-
The sulfidation of eight carboxylic and carbonic acid amides (A-H) with bis(1,5-cyclooctanediylboryl) sulfide (1) is described.From the aliphatic acyclic amide A and the N-substituted lactams C-E the corresponding thiocarbonyl compounds 2a and 2c-e, resp.
- Koester, Roland,Kucznierz, Ralf
-
p. 1081 - 1086
(2007/10/02)
-
- Manganese dioxide in a new role of Sulfur extrusion in thioamides
-
A simple and efficient procedure for the mild conversion of thioamides to amides in good yields using active manganese dioxide is described.
- Radha Rani,Rahman,Bhalerao
-
p. 1953 - 1958
(2007/10/02)
-
- New 5-nitroimidazoles bearing lactame nucleus: Synthesis and antibacterial properties
-
New 5-nitroimidazoles bearing a trisubstituted ethylenic double bond in position 2 were prepared by reacting various 1-alkyl-2-chloromethyl-5-nitroimidazole with 3-nitrolactam anions by S(RN)1 mechanism in phase-transfer catalysis conditions. These compounds showed in vitro and in vivo antianaerobic activity which was clearly greater than that of metronidazole. Structure-activity relationships have been discussed.
- Jentzer,Vanelle,Crozet,Maldonado,Barreau
-
p. 687 - 697
(2007/10/02)
-
- In Situ Reagent for Thionation of Amides, Peptides and Lactams
-
An in situ reagent 1A for thionation of amides, peptides and lactams is prepared from phosphorus decasulfide/sodium carbonate (1:1 ratio) in THF at 25 deg C.
- Brillon, Denis
-
p. 3085 - 3095
(2007/10/02)
-
- 2,4-Bis(4-methylphenylthio)-1,3,2λ5,4λ5-dithiadiphosphetane-2,4-dithione: A New Reagent for Thiation of N,N-Disubstituted Amides
-
As a new reagent for the thiation of amides, the easily accessible 2,4-bis(4-methylphenylthio)-1,3,2λ5,4λ5-dithiadiphosphetane-2,4-dithione (9) shows a remarkable selectivity.This selectivity - the preferred thiation of N,N-disubstituted amides - is complementary to the one of the well known Lawesson reagent.Thiation of diamides of type 2 with 9 leads via cyclization of the corresponding dithiodiamides directly to 1,3-thiazole-5(4H)-thiones 1.
- Wipf, Peter,Jenny, Christjohannes,Heimgartner, Heinz
-
p. 1001 - 1011
(2007/10/02)
-
- Synthesis of Unsymmetrical Functionalised Organic Sulphides
-
Acyclic thioiminium salts and the condensed thiazolium salts in the presence of aqueous sodium hydroxide as such or under base catalyzed phase transfer catalysis conditions react with appropiate organic halides to provide corresponding unsymmetrical functionalized organic sulphides.With aqueous sodium hydroxide, thioiminium salts provide the disulphides corresponding to incipient thiol.
- Singh, Harjit,Batra, Manohar S.,Singh, Paramjit
-
p. 131 - 136
(2007/10/02)
-
- STUDIES ON ORGANOPHOSPHORUS COMPOUNDS XLVII PREPARATION OF THIATED SYNTHONS OF AMIDES, LACTAMS AND IMIDES BY USE OF SOME NEW P,S-CONTAINING REAGENTS
-
The thionation properties of 2,4-bismethylthio-1,3,2,4-dithiadiphosphetane 2,4-disulfide, 1, 2,4-bis(4-phenoxyphenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide, 2, 2,4-bis(4-phenylthiophenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide, 3, and 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiaphosphetane 2,4-disulfide (LR), 4, have been investigated on a series of amides, lactams and imides.The most remarkable feature is that 2, 3 and 4 thionate most amides and lactams in THF at room temperature (reaction time 5 min) to give the corresponding thionated compounds.Imides are easily thionated by 2, 3 and 4 in DME at 60 oC.The reactions of 1 with amides, imides and most lactams are run at 60 oC to give good yields of the corresponding thionated compounds.
- Yde, B.,Yousif, N. M.,Pedersen, U.,Thomsen, I.,Lawesson, S. -O.
-
p. 2047 - 2052
(2007/10/02)
-
- Note on the Preparation of N,N-Disubstituted Aliphatic Thiocarboxamides, N-Substituted Thiolactames, and Aromatic Thiocarboxylates
-
Hydrogen sulfide reacts with the N,N-dimethylformamide acetal 1 to give N,N-(dimethyl)thioformamide (2a).The thioamides 2a-e and the thiolactams 2f,g are prepared by thiolysis of the nitriles 3a-g.The action of hydrogen sulfide on nitriles 5a-f affords the O-ethyl thiocarboxylates 6a-f.The preparation of the nitriles 3g and 5a-f is described.
- Kantlehner, Willi,Haug, Erwin,Farkas, Michael
-
p. 1582 - 1587
(2007/10/02)
-
- UNSATURATED THIOLATES AND THEIR ANALOGS IN CYCLOADDITION REACTIONS XI. EFFECT OF SUBSTITUENTS AT THE β POSITION OF ETHENETHIOLATES ON THE DIRECTION OF REACTION WITH CARBON BISULFIDE
-
1-Dialkylamino-, 1-alkylarylamino-, and 1-cycloalkylaminoethenethiolates react with carbon bisulfide in various directions, depending on the nature of the substituents at the position 2.In all cases 1,2-dithiole-3-thiones are formed.Thiolates unsubstituted at position 2 give, in addition, 5,5'-bis(dialkylamino)-, 5,5'-bis(alkylarylamino)-, and 5,5'-bis(cycloalkylamine)-1,1',2,2'-tetrathiafulvalenes.In the case of potassium 1-morpholino-2-tert-butylethenethiolate the reaction is accompanied by the elimination of a molecule of morpholine and by the formation of 4-tert-butyl-1,2-dithiole-3-thione.In the presence of a weak proton donor (acetonitrile) ethylenethiolates substituted at position 2 react normally, but the 1-piperidinoethenethiolate gives mainly N,N-pentamethylenetrithiomalonamide.
- Bobylev, V. A.,Petrov, M. L.,Petrov, A. A.
-
p. 239 - 245
(2007/10/02)
-
- Breakdown of Hemiorthothiamide Tetrahedral Intermediates Derived from O,N-Dimethyllactamium Tetrafluoroborates
-
The sulfhydrolytic cleavage of O,N-dimethylbutyrolactamium and O,N-dimethylvalerolactamium tetrafluoroborates involves C-N scission under kinetic control (61 deg C, NaSH, Ac2O, CHCl3) but C-O cleavage under thermodynamic control (27 deg C, NaSH, acetone).
- Kaloustian, Moses K.,Nader, Randa B.
-
p. 5050 - 5052
(2007/10/02)
-
