Room-Temperature Electrophilic 5-<i>endo</i>-<i>dig</i>Chlorocyclization of Alk-3-yn-1-ones with the Use of Pool Sanitizer: Synthesis of 3-Chlorofurans and 5-Chlorofuropyrimidine Nucleosides
作者:Adam Sniady、Marco S. Morreale、Kraig A. Wheeler、Roman Dembinski
DOI:10.1002/ejoc.200800397
日期:2008.7
chlorocyclization of 1,4-disubstituted alk-3-yn-1-ones (propargylic ketones) with the use of trichloro-s-triazinetrione (trichloroisocyanuric acid, TCCA; 0.4 equiv.) in toluene, at room temperature, in the absence of base, provides 2,5-disubstituted 3-chlorofurans in high yields (79–96 %). The reaction can be accomplished by using commercially available swimming poolsanitizer. Selected 3-chlorofuran was validated
A one-pot tandem Wittig/conjugate reduction/PaalKnorr reaction is reported for the synthesis of di- or trisubstituted furans. This novel sequence first demonstrates the possibility of successively recycling waste from upstream steps to catalyze downstream reactions.
Brønsted Acid-Catalyzed Cycloisomerization of But-2-yne-1,4-diols with or without 1,3-Dicarbonyl Compounds to Tri- and Tetrasubstituted Furans
作者:Srinivasa Reddy Mothe、Sherman Jun Liang Lauw、Prasath Kothandaraman、Philip Wai Hong Chan
DOI:10.1021/jo301093f
日期:2012.8.17
efficiently from cycloisomerization of but-2-yne-1,4-diols with or without 1,3-dicarbonyl compounds is described. By taking advantage of the orthogonal modes of reactivity of the alcoholic substrate through slight modification of the reaction conditions, a divergence in product selectivity was observed. At roomtemperature, p-TsOH·H2O-mediated tandem alkylation/cycloisomerization of the propargylic
Substituent and wavelength effects in the photochemistry of 5,6,7,8-tetrachloro-3a,9a-dihydro-2,3,9a-triarylfuro(2,3-b)(1,4)benzodioxin derivatives
作者:William M. Horspool、Abedawn I. Khalaf
DOI:10.1016/s0040-4039(00)94524-6
日期:1983.1
A study of the photoreactions of some triarylfurobenzodioxin derivatives has shown that the outcome is dependent on the type and position of the substitution on the 9a-aryl group. A wavelength dependence is also reported.