69836-64-2Relevant academic research and scientific papers
Scope of the suzuki-Miyaura cross-coupling reactions of potassium heteroaryltrifluoroborates
Molander, Gary A.,Canturk, Belgin,Kennedy, Lauren E.
supporting information; experimental part, p. 973 - 980 (2009/07/11)
A wide variety of bench-stable potassium heteroaryltrifluoroborates were prepared, and general reaction conditions were developed for their cross-coupling to aryl and heteroaryl halides. The cross-coupled products were obtained in good to excellent yields. This method represents an efficient and facile installation of heterocyclic building blocks onto preexisting organic substructures.
Synthesis of allenyl ketones and their palladium-catalyzed cycloisomerization/dimerization: Approaching the limits
Hashmi, A. Stephen K.,Choi, Ji-Hyun,Bats, Jan W.
, p. 342 - 357 (2007/10/03)
The preparation of several new allenyl ketones 1a-j and 1o-q is reported. In the case of allenyl ketones with nucleophilic groups in the side-chain like 1k-m, the material polymerized during the purification procedure; with the dialkyl thioether In the product of a Pummerer isomerization, the acetoxymethyl alkyl thioether, 11 was formed. Depending on the route to 1 sometimes either the acetate adducts 8 and the 1-propynyl ketones 9 or the dipropargyl and propargyl allenyl carbinol 14 and 15 were observed as side-products. Good yields of the sensitive aryl γ-halogen-allenyl ketones 23a and 23b were obtained by a new synthetic route, on the other hand the aryl γ-silylallenyl ketone 23c was readily desilylated. Subjecting the new allenyl ketones to the PdCl2(MeCN)2 catalyst provided the 2-substituted furans 2 and the 2,4-disubstituted furans 3 in most cases. The yields and ratios of these products strongly depended on the nature of the groups being present. With the aryl thioether and the γ-halogen allenyl ketones the palladium-catalyzed reaction failed. Detailed structural information about the new products was provided by the X-ray structure analyses of the p-acetamidophenyl propargyl carbinol 6g and the 2-aryl-4-(1-methyl-3-aryl-3-oxo-propen-1-yl furan 3h. Wiley-VCH Verlag GmbH, 1999.
ELECTROOXIDATION OF 2-ARYLFURANS
Janda, Miroslav,Srogl, Jan,Dvorakova, Hana,Dvorak, Dalimil,Stibor, Ivan
, p. 906 - 916 (2007/10/02)
Electrochemical methoxylation of 2-phenylfuran (I) and 2-(4-nitrophenyl)furan (VI) proceeded anomalously, affording 5-methoxy-2-phenylfuran (XI) and 5-methoxy-2-(4-nitrophenyl)furan (XIII), respectively. 2-Phenyl-5-methylfuran (II) and methyl-2-(2-methylphenyl)-3-furoate (VIII) behaved normally giving the respective 2,5-dimethoxy-2,5-dihydrofuran derivatives XII and XIV.The suggested ECNECB mechanism of the anomalous methoxylation was confirmed by methoxylation of compound II, in which the methyl group hinders the last CB step, and also of compound VIII in whichthe aromaticity is suppresed by forced deviation from planarity.Forced deviation from planarity was moreover studied also on 2-(4-methylphenyl)furan (III), 5-methyl-2-(2-methylphenyl)furan (IV) and 3,5-dimethyl-2-(2-methylphenyl)furan (V) as model compounds.For all the derivatives the INDO charges were calculated and correlated with the 1H- and 13C-NMR spectra.The experimental electronic spectra were correlated with the theoretical ones (INDO-S-CI).All results obtained confirm the suggested mechanism.
