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ABSTRACT: Difunctionalization: Inexpensive and environmentally benign FeCl(3) catalyzes the oxidative 1,2-alkylarylation of activated alkenes with an aryl C(sp(2) )H bond and a C(sp(3) )H bond adjacent to a heteroatom. This reaction is a new strategy for the synthesis of oxindoles and makes use of DBU as ligand and TBHP as oxidant (see scheme, TBHP=tert-butyl hydrogenperoxide).
Angewandte Chemie International Edition 02/2013; · 13.45 Impact Factor
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ABSTRACT: Ray of light: 10a,11-dihydro-10H-benzo[b]fluorenes were synthesized by a visible-light catalyzed tandem cyclization of 1,6-enynes with arylsulfonyl chlorides. This method extends the scope of enyne cyclizations and represents a new synthetic application of arylsulfonyl chlorides.
Angewandte Chemie International Edition 01/2013; · 13.45 Impact Factor
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ABSTRACT: Open a new door: The first example of alkene synthesis from alkyl electrophiles with Grignard reagents using the Kumada cross-coupling reaction strategy is reported. This method opens a new door for the Kumada cross-coupling reaction, allowing alkenes to be prepared from the reaction of tosylalkanes with Grignard reagents.
Angewandte Chemie International Edition 09/2012; 51(39):9909-13. · 13.45 Impact Factor
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ABSTRACT: A new, general method for the synthesis of spiro[4,5]trienones is described by the intramolecular ipso-halocyclization of 4-(p-unsubstituted-aryl)-1-alkynes. In the presence of halide electrophiles, a variety of 4-(p-unsubstituted-aryl)-1-alkynes underwent the intramolecular ipso-halocyclization with water smoothly, affording the corresponding halo-substituted spiro[4,5]trienones in moderate to good yields. The obtained spiro[4,5]trienones can be applied in constructing the azaquaternary tricyclic skeleton via Pd-catalyzed Heck reaction. Notably, the prepared spiro[4,5]trienones and azaquaternary tricycles are of importance in the areas of pharmaceuticals and agrochemicals. The mechanism of the intramolecular ipso-halocyclization reaction is also discussed according to the (18)O-labeling experiments and DFT calculations.
The Journal of Organic Chemistry 03/2012; 77(6):2837-49. · 4.45 Impact Factor
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ABSTRACT: Keeping options open: The new and mild title reaction involving indoles selectively furnishes 1 and 2 with the aid of tert-butyl hydroperoxide (TBHP). The method represents the first example of a copper-catalyzed α arylation of α-amino carbonyl substrates leading to α-aryl α-imino and α-aryl α-oxo carbonyl compounds using a CH oxidation strategy.
Angewandte Chemie International Edition 02/2012; 51(14):3453-7. · 13.45 Impact Factor
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ABSTRACT: The first example of Ru-catalyzed intramolecular annulation of alkynes with amides via formyl translocation has been developed, which provides an efficient approach for the synthesis of 1H-indole-3-carbaldehydes.
Chemical Communications 02/2012; 48(26):3197-9. · 6.17 Impact Factor
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ABSTRACT: A new palladium-catalyzed C-H bond activation-annulation-amination tandem method was presented for selectively synthesizing 3-(aminomethylene)-2-oxoindolines. In the presence of Pd(dba)(2), xantphos (L8), AgOAc and Na(2)CO(3), a variety of 3-chloro-2-iodo-N-arylacrylamides underwent the reaction with amides or amines to afford the corresponding 3-(aminomethylene)-2-oxoindolines in moderate to good yields.
Chemical Communications 06/2011; 47(28):8151-3. · 6.17 Impact Factor
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ABSTRACT: A new, selective method for the synthesis of (E)-vinyl sulfones is presence by palladium-catalyzed C-S bond cleavage/conjugate addition. In the presence of Pd(OAc)(2) and DMEDA (N(1),N(2)-dimethylethane-1,2-diamine), 1,2-bis(phenylsulfonyl)ethane underwent the C-S bond cleavage, followed by conjugate addition to numerous electron-deficient alkynes afforded the corresponding (E)-vinyl sulfones in moderate to good yields.
The Journal of Organic Chemistry 02/2011; 76(3):1001-4. · 4.45 Impact Factor
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ABSTRACT: An iron-mediated tandem annulation strategy has been developed for the synthesis of numerous functional indeno[1,2-c]chromenes and 5H-naphtho[1,2-c]chromenes. This work is the first to disclose an iron-mediated method through sequential electrophilic addition of a ketone to an alkyne and annulation tandem reaction. Importantly, a halide is introduced into the products by a ring-opening process among the annulation of alkynylcyclopropanes, which makes the methodology more attractive for organic synthesis.
Organic Letters 01/2011; 13(1):14-7. · 5.86 Impact Factor
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ABSTRACT: Palladium-catalyzed annulations of arynes with 2-(2-iodophenoxy)-1-substituted ethanones for the synthesis of 6H-benzo[c]chromenes are presented. This mild route allows formation of two new carbon-carbon bonds via an α-arylation/annulation process.
Chemical Communications 11/2010; 46(43):8183-5. · 6.17 Impact Factor
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ABSTRACT: A new, efficient Cu-catalyzed intramolecular C-H oxidation/acylation method has been developed for the synthesis of substituted indoline-2,3-diones (isatins). In the presence of CuCl(2) and O(2), a variety of formyl-N-arylformamides underwent the tandem reaction to afford the corresponding indoline-2,3-diones in moderate to good yields. It is noteworthy that the reaction serves as the first example of transition-metal-catalyzed transformation for the preparation of indoline-2,3-diones.
Journal of the American Chemical Society 07/2010; 132(26):8900-2. · 9.91 Impact Factor
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Advanced Synthesis & Catalysis 11/2009; 351(18):3096 - 3100. · 6.05 Impact Factor
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ABSTRACT: A copper/silver-catalyzed Conia-ene reaction has been developed for selectively constructing five-membered and six-membered rings. In the presence of (CuOTf)(2) x C(6)H(6) and AgBF(4), a variety of 2-alkynic 1,3-dicarbonyl compounds underwent the Conia-ene intramolecular reaction smoothly in moderate to good yields. It is noteworthy that both 2-phenylacetylhept-6-ynenitrile and diethyl 2-(pent-4-ynyl)malonate are also suitable substrates under the standard conditions, and the selectivity toward endo- or exo-products depends on the substituents at the terminal of alkynes.
The Journal of Organic Chemistry 12/2008; 74(1):412-4. · 4.45 Impact Factor
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ABSTRACT: A novel and general copper/silver catalytic system has been developed for the Conia-ene intramolecular reaction of linear beta-alkynic beta-ketoesters. In the presence of (CuOTf)2.C6H6 and AgSbF6 (or AgOAc), a variety of the linear beta-alkynic beta-ketoesters selectively underwent the Conia-ene intramolecular reaction in moderate to good yields.
Organic Letters 12/2007; 9(24):5111-4. · 5.86 Impact Factor
