42249-98-9Relevant academic research and scientific papers
A combined experimental and theoretical analysis on the solid-state supramolecular assemblies of pent?2-ynol derivatives
Bardhan, Soumik,Bera, Nabakumar,Klecker, Jan Christopher,Reuter, Hans,Sarkar, Debayan,Seth, Saikat Kumar
, (2021)
Two new compounds namely, 6-methyl-1-(p-tolyl)hept?3?yne-1,5-diol (1) and N-(5?hydroxy-1-phenylhex-3-yn-1-yl)-4-nitrobenzenesulfonamide (2) have been synthesized and structurally characterized through single-crystal X-ray diffraction analysis. X-ray cryst
Stereodivergent Palladium- And Rhodium-Catalyzed Intramolecular Addition of Tosylureas to Allenes: Diastereoselective Synthesis of Tetrahydropyrimidinones
Breit, Bernhard,Geissler, Arne G. A.,Riesterer, Jasmin R.
supporting information, p. 9168 - 9172 (2021/12/06)
The intramolecular addition of tosylureas to allenes is highly syn-/anti-diastereoselective when employing a palladium or rhodium-based catalytic system and affords 1,3-cyclic ureas. Under palladium catalysis a range of thermodynamic anti-tetrahydropyrimi
Silylcyclopropanes by Selective [1,4]-Wittig Rearrangement of 4-Silyl-5,6-dihydropyrans
Mori-Quiroz, Luis M.,Maloba, Emmanuel W.,Maleczka, Robert E.
supporting information, p. 5724 - 5728 (2021/07/31)
4-Silyl-5,6-dihydropyrans undergo remarkably selective [1,4]-Wittig rearrangements to give silylcyclopropanes in good yields. The selectivity is independent of the silyl group, but it is influenced by the electronic character of the migrating center. Elec
One-Pot γ-Lactonization of Homopropargyl Alcohols via Intramolecular Ketene Trapping
Yamane, Daichi,Tanaka, Haruna,Hirata, Akihiro,Tamura, Yumiko,Takahashi, Daichi,Takahashi, Yusuke,Nagamitsu, Tohru,Ohtawa, Masaki
supporting information, p. 2831 - 2835 (2021/05/05)
A one-pot γ-lactonization of homopropargyl alcohols via an alkyne deprotonation/boronation/oxidation sequence has been developed. Oxidation of the generated alkynyl boronate affords the corresponding ketene intermediate, which is trapped by the adjacent hydroxy group to furnish the γ-lactone. We have optimized the conditions as well as examined the substrate scope and synthetic applications of this efficient one-pot lactonization.
Allenone-Mediated Racemization/Epimerization-Free Peptide Bond Formation and Its Application in Peptide Synthesis
Wang, Penghui,Wang, Xuewei,Wang, Zhengning,Zhao, Junfeng
supporting information, p. 10374 - 10381 (2021/07/26)
Allenone has been identified as a highly effective peptide coupling reagent for the first time. The peptide bond was formed with an α-carbonyl vinyl ester as the key intermediate, the formation and subsequent aminolysis of which proceed spontaneously in a racemization-/epimerization-free manner. The allenone coupling reagent not only is effective for the synthesis of simple amides and dipeptides but is also amenable to peptide fragment condensation and solid-phase peptide synthesis (SPPS). The robustness of the allenone-mediated peptide bond formation was showcased incisively by the synthesis of carfilzomib, which involved a rare racemization-/epimerization-free N to C peptide elongation strategy. Furthermore, the successful synthesis of the model difficult peptide ACP (65-74) on a solid support suggested that this method was compatible with SPPS. This method combines the advantages of conventional active esters and coupling reagents, while overcoming the disadvantages of both strategies. Thus, this allenone-mediated peptide bond formation strategy represents a disruptive innovation in peptide synthesis.
Formal metal-free γ-arylation of 1,3-dicarbonyl compounds: Via an isomerisation/1,4-addition/[3,3]-sigmatropic rearrangement sequence
Guan, Xi-Dong,Lu, Shi-Chao,Wen, Fu-Qiang
supporting information, p. 8964 - 8968 (2021/11/27)
A metal-free redox arylation of alkynes with sulfoxides has been developed to provide unconventional access to diverse γ-arylated 1,3-dicarbonyl compounds in an atom-economical manner. Mechanistic studies suggest that a conjugated allenone intermediate was generated in situ, which solves the problem of reactivity and regioselectivity of unsymmetrical dialkyl-substituted internal alkynes and enables the functionalisation of a broad range of substrates bearing electron-withdrawing functional groups. The resulting arylated 1,3-dicarbonyl compounds are versatile and useful building blocks for further functionalisation. This journal is
Revisiting the Addition of in-situ Nucleophiles to Allenic Ketones: An Entry Towards Synthesis of Benzodioxins
Sahoo, Sushree Ranjan,Sarkar, Debayan
supporting information, p. 1727 - 1731 (2020/03/13)
The manuscript delineates a revisit towards regioselective addition of in situ generated negative nucleophiles to allenic ketones in the presence of a base. A wide variety of allenic ketones as well as nucleophiles are viable in this transformation. A dir
Acyloxy Rearrangement-Triggered Regioselective Hydration of ?-Acetoxy-α,β-Alkynoates/Halo Alkynes
Mendhekar, Kishor L.,Mohapatra, Debendra K.,Pradhan, Tapas R.
, p. 4881 - 4895 (2020/05/01)
Herein, we report a simple, efficient, highly regioselective, and broad-scope hydration method that is facilitated by an unusual interception of an electrophilic intermediate by water generated via acetate group participation during [3,3]-acyloxy rearrang
Synthesis, characterization of active Sn(0), and its application in selective propargylation of aldehyde at room temperature in water
Chatterjee, Paresh Nath,Paul, Dipankar,Sawkmie, Micky Lanster,Sinha, Arun Kumar,Khatua, Snehadrinarayan
supporting information, p. 29 - 36 (2019/01/10)
Active Sn(0) particles are synthesized in high yields by the chemical reduction of the blue-black stannous oxide using freshly prepared sodium stannite solution as reducing agent at 40 °C and 60 °C. The Sn(0) particles are characterized using powder XRD, SEM, and DSC. The as-synthesized Sn(0) particles are applied as reagent for the regioselective synthesis of homopropargyl alcohols from propargyl bromide and aldehydes in distilled water at room temperature (in 50%-84% yields). No assistance of heat, microwave, ultrasound, organic co-solvent, co-reagent, or inert atmosphere is required for this reaction. The propargylation reaction is highly chemoselective towards aldehyde over other less electrophilic carbonyl functional groups such as ketone, amide, and carboxylic acid. Our in-house synthesized homopropargyl alcohols can be used to synthesize conjugated 1,3-diynes.
Active bismuth mediated allylation of carbonyls/N-tosyl aldimines and propargylation of aldehydes in water
Sawkmie, Micky Lanster,Paul, Dipankar,Khatua, Snehadrinarayan,Chatterjee, Paresh Nath
, (2019/06/08)
Abstract: Active bismuth is synthesized by the chemical reduction of bismuth trichloride using freshly prepared sodium stannite solution as the reducing agent at room temperature. The as-synthesized active bismuth is applied as a reagent for the synthesis of homoallyl alcohol/homopropargyl alcohol from allyl bromide/propargyl bromide and carbonyl compounds in water at 50°C. The homoallyl amines are also synthesized from N-tosyl aldimines and allyl bromide using active bismuth reagent in good yields. No assistance of organic co-solvent, co-reagent, phase transfer catalyst or inert atmosphere is required for this reaction. The waste bismuth material obtained after the completion of the organic reaction can be reduced to active bismuth by sodium stannite solution and successfully reused for mediating the allylation of aldehydes. Graphical Abstract:: Synopsis Active bismuth mediated allylation/crotylation of aldehydes is developed in water to get homoallyl alcohols. The method is also applied for the allylation of N-tosyl aldimines and propargylation of aldehydes in water to achieve the homoallyl amines and homopropargyl alcohols, respectively. The reactions do not require the assistance of organic co-solvent, co-reagent, phase transfer catalyst or inert atmosphere.[Figure not available: see fulltext.].
