109-49-9Relevant academic research and scientific papers
Three-step synthetic pathway to fused bicyclic hydantoins involving a selenocyclization step
?mit, Biljana M.,Pavlovi?, Radoslav Z.
, p. 1101 - 1108 (2015)
Sequential 5-alkenyl hydantoin and pyrrolidine ring-forming reactions have been applied in the synthesis of conformationally constrained fused bicyclic scaffold. They are assembled by a three-step reaction sequence from two variable building blocks (readily available β-ketoesters and alkenyl halides) by combining a Bucherer-Bergs reaction with a final selenium-promoted intramolecular cyclization as a key step. The chemoselectivity of this bicyclic hydantoin formation is strongly influenced by experimental factors such as the solvent and the use of additives. The reaction is regiospecific giving only five-membered fused bicyclic hydantoins in good to excellent yields stemming from the nucleophilic attack of the nitrogen atom to a cyclic seleniranium ion intermediate during the cyclization step. A separable diastereomeric mixture is obtained; the products with bridgehead substituents and phenylseleno groups in cis relationships were formed predominantly. The reaction tolerates a variety of substitution at the double bond, furthermore, the presence of substituents at C(5) and N(3) position opens up the capability of generating a broad structural diversity.
FREE RADICAL CHAIN REACTION OF ALLYLIC TIN COMPOUNDS WITH ORGANIC HALIDES INVOLVING SH prime PROCESS.
Migita,Nagai,Kosugi
, p. 2480 - 2484 (1983)
Negatively substituted halomethanes were allylated easily by allyltin compounds via radical chain reaction involving S//H prime process. Aryl, aralkyl, and alkyl halides underwent similar chain reactions only when the tin compound was charged in excessive amounts.
Kinetic resolution of racemic secondary alcohols via oxidation with Yarrowia lipolytica strains
Fantin, Giancarlo,Fogagnolo, Marco,Medici, Alessandro,Pedrini, Paola,Fontana, Silvia
, p. 2367 - 2373 (2000)
Cyclic and alicyclic racemic secondary alcohols are kinetically resolved via oxidation with Yarrowia lipolytica strains. The comparison of the oxidation reactions with the reductions of the corresponding ketones supports the hypothesis of the presence of
Atroposelective Synthesis of Axially Chiral N-Arylpyrroles by Chiral-at-Rhodium Catalysis
Chen, Shuming,Han, Feng,Houk, K. N.,Ivlev, Sergei,Meggers, Eric,Xie, Xiulan,Ye, Chen-Xi
, p. 13552 - 13556 (2020)
A transformation of fluxional into configurationally stable axially chiral N-arylpyrroles was achieved with a highly atroposelective electrophilic aromatic substitution catalyzed by a chiral-at-metal rhodium Lewis acid. Specifically, N-arylpyrroles were alkylated with N-acryloyl-1H-pyrazole electrophiles in up to 93 percent yield and with up to >99.5 percent ee, and follow-up conversions reveal the synthetic utility of this new method. DFT calculations elucidate the origins of the observed excellent atroposelectivity.
Erbium(III) triflate: A valuable catalyst for the rearrangement of epoxides to aldehydes and ketones
Procopio, Antonio,Dalpozzo, Renato,De Nino, Antonio,Nardi, Monica,Sindona, Giovanni,Tagarelli, Antonio
, p. 2633 - 2635 (2004)
Rearrangement of epoxides is performed with erbium triflate as catalyst. In contrast to most proposed catalysts for this re-action, erbium triflate works well with both aromatic and aliphatic epoxides.
Polyethylene-Bound Soluble Recoverable Palladium(0) Catalysts
Bergbreiter, David E.,Weatherford, David A.
, p. 2726 - 2730 (1989)
The use of diphenylphosphine-terminated ethylene oligomers as ligands for palladium(0) and palladium(II) is described.With use of these polymeric ligands, it is possible to carry out homogeneous reactions characteristic of (Ph3P)4Pd and (Ph3P)2Pd(OAc)2 with essentially complete recovery of the Pd catalyst.The only limitation to repeated reuse of the catalyst is its immolative catalytic oxidation of the phosphine ligand by adventitious oxygen.
PALLADIUM-CATALYZED REARRANGEMENT OF ALLYLIC ESTERS OF ACETOACETIC ACID TO GIVE γ,δ-UNSATURATED METHYL KETONES
Shimizu, Isao,Yamada, Toshiro,Tsuji, Jiro
, p. 3199 - 3202 (1980)
Various allylic esters of acetoacetic acid undergo rearrangement to give γ,δ-unsaturated methyl ketones in high yields with elimination of carbon dioxide under mild conditions in the presence of catalytic amounts of Pd(OAc)2 and PPh3.
A NOVEL SYNTHESIS OF TERMINAL OLEFINS BY ANODIC OXIDATION OF CARBOXYLIC ACIDS HAVING A TRIMETHYLSILYL GROUP ON THE β-POSITION
Shono, Tatsuya,Ohmizu, Hiroshi,Kise, Naoki
, p. 1517 - 1520 (1980)
Anodic oxidation of carboxylic acids having a trimethylsilyl group on the β-position gave exclusively terminal olefins in reasonable yields.
Conversion of ketoximes to ketones with trimethylphosphine and 2,2′-dipyridyl diselenide
Martín, Manuel,Martínez, Gabriel,Urpí, Fèlix,Vilarrasa, Jaume
, p. 5559 - 5561 (2004)
Use of trimethylphosphine (Me3P) and 2,2′-dipyridyl diselenide (PySeSePy) is an excellent method for the conversion of ketoximes to the corresponding ketones, since yields higher than 90% are obtained at rt within a fewminutes (or hours for the more reluctant substrates, which do not react with Bu3P/PhSSPh). In the simplest cases, the reaction can be completed with 30mol% of PySeSePy, provided that an excess of phosphine is present in the reaction medium.
An efficient method for deprotection of acetals
Saravanan,Chandrasekhar,Anand, R. Vijaya,Singh, Vinod K.
, p. 3091 - 3092 (1998)
A variety of acetonides and acetals were efficiently cleaved using CuCl2.2H2O in MeCN. The method was effectively used in synthesis of chiral diols which are important in asymmetric synthesis.
