46201-15-4Relevant academic research and scientific papers
Straightforward and Regioselective Access to Unsaturated α-Benzyl Butyrolactones
Talbi, Arbia,Bsaibess, Talia,Efrit, Mohamed Lotfi,M'Rabet, Hédi,Gaucher, Anne,Prim, Damien
, p. 5246 - 5251 (2017)
The efficient preparation of various substituted α-benzyl unsaturated butyrolactones is described. The palladium-mediated C–C bond formation that uses α-bromomethylbutenolide and boron derivatives as coupling partners accounts for the key step of this syn
Dual Activity of Grubbs-Type Catalyst in the Transvinylation of Carboxylic Acids and Ring-Closing Metathesis Reactions
Brodzka, Anna,Koszelewski, Dominik,Ostaszewski, Ryszard,Brodzka, Anna,Ostaszewski, Ryszard
, p. 15305 - 15313 (2020/12/01)
The development of a multifunctional catalyst, which mimics the promiscuity of enzymes, that would catalyze more than one chemical transformation in a single reaction vessel is one of the key points of modern sustainable chemistry. The results of our experiments indicated that Grubbs-type catalysts possess such multitask activity, catalyzing the transvinylation reaction of carboxylic acids without losing their original metathetic activity. This new activity of Grubbs catalysts was evidenced on several examples. It allows us to design a transvinylation/ring-closing metathesis (RCM) cascade reaction leading to the formation of endocyclic enol lactones from unsaturated carboxylic acids in an one-pot procedure. This unique ability of Grubbs catalyst to catalyze multiple mechanically distinct cascade reactions in a chemoselective way offers the new possibility for the synthesis of complex compounds from simple, easily accessible substrates.
Studies on the Synthesis of Endocyclic Enol Lactones via a RCM of Selected Vinyl Esters
Brodzka, Anna,Borys, Filip,Koszelewski, Dominik,Ostaszewski, Ryszard
, p. 8655 - 8661 (2018/06/22)
The novel and efficient approach toward the synthesis of endocyclic enol lactones was devised based on ring-closing metathesis of unsaturated carboxylic acids vinyl esters. Systematic studies revealed that vinyl esters are suitable substrates for RCM reaction. The developed methodology offers an easy route for synthetically challenging target molecules with different functional groups and substitution. We have also demonstrated that vinyl esters of cyclic carboxylic acids can be successfully applied for domino ring-opening ring-closing metathesis sequences.
Asymmetric hydrogenation of α,β-unsaturated carboxylic esters with chiral iridium N,P ligand complexes
Woodmansee, David H.,Mueller, Marc-Andre,Troendlin, Lars,Hoermann, Esther,Pfaltz, Andreas
supporting information, p. 13780 - 13786 (2013/01/15)
Enantioselective conjugate reduction of a wide range of α,β-unsaturated carboxylic esters was achieved using chiral Ir N,P complexes as hydrogenation catalysts. Depending on the substitution pattern of the substrate, different ligands perform best. α,β-Unsaturated carboxylic esters substituted at the α position are less problematic substrates than originally anticipated and in some cases α-substituted substrates actually reacted with higher enantioselectivity than their β-substituted analogues. The resulting saturated esters with a stereogenic center in the α or β position were obtained in high enantiomeric purity. Copyright
Tailoring nostoclide structure to target the chloroplastic electron transport chain
Barbosa, Luiz C. A.,Varejao, Jodieh O. S.,Petrollino, Davide,Pinheiro, Patricia F.,Demuner, Antonio J.,Maltha, Celia R. A.,Forlani, Giuseppe
scheme or table, p. 15 - 32 (2012/03/10)
Aiming to improve their effectiveness, three modifications were introduced into the structure of the natural phytotoxins nostoclides, leading to the synthesis of novel 3-benzyl-4-isopropyl-5- (arylmethylene)furan-2(5H)-ones, 3-benzyl-5-(furan-2-ylmethylene)furan-2(5H)-ones, and 3,4 dihalo-5- arylidenefuran-2(5H)-ones. All compounds were characterized by IR, 1H and 13C NMR, NOEDIF, COSY, HETCOR and MS spectrometry. Increasing the length of the molecule was found to reduce the ability to interfere with ferricyanide reduction by isolated chloroplasts. The addition of an isopropyl moiety into the heterocyclic ring, as in naturally-occurring nostoclides, did not influence the inhibitory potential. Also the replacement of the electron-drawing phenyl substituent with two halogen residues did not improve the resulting activity. However, both latter modifications influenced the interaction with the photosynthetic machinery. These analogues could therefore represent novel leads to be explored toward the development of new herbicides targeting the chloroplastic electron transport chain. ARKAT-USA, Inc.
General, regiodefined access to α-substituted butenolides through metal-halogen exchange of 3-bromo-2-silyloxyfurans. Efficient synthesis of an anti-inflammatory Gorgonian lipid
Boukouvalas, John,Loach, Richard P.
, p. 8109 - 8112 (2008/12/22)
(Chemical Equation Presented) A variety of α-substituted butenolides were efficiently prepared from 3-bromo-2-triisopropylsilyloxyfuran via lithium-bromine exchange and in situ quench with carbon or heteroatom electrophiles. The inherent flexibility of this methodology is illustrated by a short and efficient synthesis of an anti-inflammatory marine natural product.
Synthesis of photosynthesis-inhibiting nostoclide analogues
Teixeira, Robson R.,Barbosa, Luiz C. A.,Forlani, Giuseppe,Pilo-Veloso, Dorila,Carneiro, Jose Walkimar De Mesquita
scheme or table, p. 2321 - 2329 (2009/12/29)
A series of 34 3-benzyl-5-(arylmethylene)furan-2(5H)-ones, designed using the naturally occurring toxins nostoclides as a lead structure, was synthesized as potential inhibitors of the photosynthetic electron transport. All compounds were fully characterized by IR, NMR (1H and 13C), and MS spectrometry. HMBC and HSQC bidimensional experiments allowed 13C and 1H assignments. Their biological activities were evaluated in vitro as the ability to interfere with light-driven reduction of ferricyanide by isolated spinach chloroplasts. About two-thirds of the compounds exhibited inhibitory properties in the micromolar range against the basal electron flow from water to K3[Fe(CN)6]. The inhibitory potential of these 3-benzyl-5-(arylmethylene)furan-2(5H)-one lactones is higher than that of other nostoclide analogues previously synthesized in the same laboratories.
Synthesis and structural characterization of two nostoclide analogues
Teixeira,Barbosa,Santana,Veloso,Ellena,Doriguetto,Drew,Ismail
, p. 197 - 205 (2007/10/03)
The vinylogous aldol reaction between appropriate aldehydes and furan-based silyloxy diene synthon generated from 3-benzyl-5H-furan-2-one (3) afforded two truncated lactone analogues [compounds (4) and (5)] of nostoclides (2). The compounds were fully cha
Synthesis of substituted 3-furan-2(5H)-ones via an anthracene Diels-Alder sequence
Jones, Simon,Wilson, Ian
, p. 4377 - 4380 (2007/10/03)
Deprotonation then electrophilic quench of the lactone derived from the Diels-Alder addition adduct of anthracene and maleic anhydride gave α-substituted lactones in good yield. Of particular note was the reaction with chlorotrimethylsilane which gave only the C-silylated product. Flash vacuum pyrolysis (FVP) of the alkylated products afforded 3-substituted furan-2(5H)-ones in good overall yield.
Preparation of selenoxides from the catalytic autoxidation of organoselenides with nitrogen oxides
Bosch, Eric,Kochi, Jay K.
, p. 2731 - 2738 (2007/10/03)
Various alkyl, aryl and benzyl selenides (RSeR') are readily coverted in high yields to the corresponding selenoxide in the presence of dioxygen and catalytic amounts of either nitrogen dioxide, nitrosonium cation or nitric oxide in acetic acid.The selenoxides are initially isolated as the acetic acid adducts (from which the free selenoxides are readily liberated by treatment with base).Nitrogen dioxide is also capable of the stoichiometric oxidation of the selenoethers; and the electron donor-acceptor or EDA complex with nitrosonium, i.e. NO3(1-) is formed as the first intermediate by the selenoether-induced disproportionation of NO2.The critical role of the nitrosonium EDA complex is further demonstrated by the production of selenoxide by an alternative (low-temperature) photochemical procedure involving the deliberate irradiation of the charge-transfer absorption band of NO3(1-).A scheme is shown that presents the sequence of redox changes of the nitrogen oxides involved in the catalytic conversion of selenoethers to their selenoxides.
