55314-57-3Relevant academic research and scientific papers
One-pot mild and efficient synthesis of [1,3]thiazino[3,2-: A] indol-4-ones and their anti-proliferative activity
Rhodes, Steven,Short, Spencer,Sharma, Sidhika,Kaur, Ramneet,Jha, Mukund
supporting information, p. 3914 - 3920 (2019/04/30)
A base mediated environmentally benign one-pot efficient methodology has been developed for the synthesis of [1,3]thiazino[3,2-a]indol-4-ones using indoline-2-thiones and propiolate esters in aqueous medium. The conjugate addition of thiones first results in ethyl (3-(indol-2-yl)thio)acrylates in situ, which subsequently undergoes intramolecular cyclization to produce indole-fused thiazin-4-ones in good to excellent yields. The cytotoxic screening of the synthesized compounds using MTT assay revealed the anti-proliferative nature of these frameworks against triple negative breast cancer cell lines with the highest activity emanating from 4H-[1,3]thiazino[3,2-a]indol-4-one and 8-methyl-2-propyl-4H-[1,3]thiazino[3,2-a]indol-4-one compounds.
Mild propargylic oxidation using a diacetoxyiodobenzene/tert-butyl hydroperoxide protocol
Zhao, Yi,Ng, Angela Wan Ting,Yeung, Ying-Yeung
, p. 4370 - 4372 (2014/07/22)
A mild propargylic oxidation of alkynes is reported using a diacetoxyiodobenzene/tert-butyl hydroperoxide (DIB/TBHP) protocol. The reactions proceed smoothly at 0 °C and a number of α,β-unsaturated alkynoic ketones are obtained.
Selective one-pot synthesis of allenyl and alkynyl esters from β-ketoesters
Maity, Pradip,Lepore, Salvatore D.
supporting information; experimental part, p. 158 - 162 (2009/04/07)
(Chemical Equation Presented) A convenient method is described for the dehydration of β-ketoesters to generate conjugated and deconjugated alkynyl esters and conjugated allenyl esters. This sequential one-pot method involves the formation of a vinyl trifl
Deprotonation of β,β-disubstituted α,β-unsaturated amides -Mechanism and stereochemical consequences
Green, James R.,Majewski, Marek,Snieckus, Victor
, p. 1397 - 1410 (2007/10/03)
A detailed study of the lithium dialkylamide induced deprotonation of β,β-disubstituted α,β-unsaturated amides is presented. The preferential γ-Z-deprotonation and stereochemical outcome of substituents on the γ-Z carbon atom are rationalized in terms of a cyclic eight-membered transition state, which is supported by DFT calculations. Analogous deprotonations on cyclohexylidenecarboxamides reveal a delicate balance of the preference for the eight-membered cyclic transition state with the effects of existing substituents on the ring and the intervention of a twist-boat transition state.
Deconjugative Alkylation of α,β-Acetylenic Esters by Electrogenerated Base
Tokuda, Masao,Nishio, Osamu
, p. 1592 - 1596 (2007/10/02)
Electrolysis of ethyl propiolate (1) and an excess of methyl iodide at a platinum cathode in hexamethylphosphoric triamide (HMPA) or N,N-dimethylformamide (DMF) solution containing tetra-n-butylammonium salt gave the acetylenic esters 2, 3, and 4.Similar electrochemical reactions of α,β-acetylenic esters 2, 5, and 9 with methyl iodide took place in good yields to give the corresponding α,α-dimethyl-β,γ-acetylenic esters 3 and 4, 4, and 10, respectively.Electrochemical reactions of 5 with ethyl, butyl, and allyl iodides also gave α,α-dialkyl β,γ-acetylenic esters 6, 7, and 8, respectively.These facile deconjugative alkylations appeared to take place by the action of the electrogenerated base (EGB) which was formed by the electrochemical reduction of alkyl iodides.Alkyl iodides worked as both a probasic compound of the EGB and as an electrophile.Reaction pathways of the present deconjugative alkylations are also discussed.
REACTION OF KETOCARBOXYLIC ACIDS AND THEIR ESTERS WITH SULFUR TETRAFLUORIDE. III. REACTION OF DERIVATIVES OF ACETOACETIC ESTER WITH SULFUR TETRAFLUORIDE
Bloshchitsa, F. A.,Burmakov, A. I.,Kunshenko, B. V.,Alekseeva, L. A.,Yagupol'skii, L. M.
, p. 679 - 684 (2007/10/02)
In the reaction of acetoacetic and propionylacetic ethyl esters with sulfur tetrafluoride compounds with a triple bond are formed in addition to the corresponding β,β-difluoroderivatives.In the case of α-alkylacetoacetic esters products containing cumulative double bonds are formed.
Solvolysis of 1-pent-3-ynyl triflate. Mechanism of the homopropargyl rearrangement
Hanack, Michael,Collins, Clair J.,Stutz,Benjamin, Ben M.
, p. 2356 - 2360 (2007/10/02)
1-Pent-3-ynyl triflate (1b) was solvolyzed (25°C, 24 h) in ethanol-water with 2,6-lutidine as the buffer. Products were formed predominantly (97-98.5%) through direct substitution (ks processes) and elimination. As the water content increases, the yields of 2-methylcyclobutanone (7b) (formed through kΔ processes) also increase from 0.2% (100% ethanol) to 2.8% (50% ethanol). 1-Pent-3-ynyl triflate was solvolyzed in anhydrous trifluoroethanol (25°C, 24 h) in nine different experiments with nine different buffers. Sodium and calcium carbonate, 2,6-lutidine, pyridine, and quinoline all favored kΔ processes (88-65%), whereas potassium carbonate, triethylamine, and sodium trifluoroethoxide suppressed the formation of rearranged products. The products of the solvolyses include: 2-methylcyclobutenyl trifluoroethyl ether (5b); cyclopropyl methyl ketone (6b); 2-methylcyclobutanone (7b); pent-1-en-3-yne (13); 1-pent-3-ynol (15); 2-methylcyclobutanone bis(trifluoroethyl) acetal (16), and 1-pent-3-ynyl trifluoroethyl ether (17). In 80% trifluoroethanol-20% water (sodium carbonate buffer) the yields of rearranged products (kΔ) dropped to 46% - as expected for an increase in nucleophilicity of the solvent. A quantitative correlation exists between percent rearrangement of 1b and nucleophilicity of the solvent, as demonstrated by use of the Winstein-Grunwald-Swain equation. 1-Pent-3-ynyl triflate was synthesized with carbon-14 in the 1 position (1b-1-14C) and, separately, in the 3 position (1b-3-14C). 1-Pent-3-ynyl triflate was also prepared doubly labeled both with carbon-14 and with deuterium (1b-3-14C-1,1-d2). Isotope effects were determined for all isotope position isomers. These are: k/*k = 1.048 ± 0.003 (1b-1-14C); k/*k = 0.990 ± 0.005 (1b-3-14C); and Hk/Dk = 1.098 ± 0.004 (1b-1,1-d2). In addition, 1b-1,1-d2 on solvolysis in trifluoroethanol-sodium carbonate yields 2-methylcyclobutanone (7b) containing equal fractions of 7b-3-d2 and 7b-4-d2. The tracer and isotope effect experiments confirm the mechanistic conclusions arrived at through product distribution studies and, in addition, offer strong evidence for significant anchimeric assistance during the kΔ processes investigated.
