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1.
Functionalized 2,5-dihydrobenzo[b]oxepins and 5,6-dihydro-2H-benzo[b]oxocines were prepared based on a ‘[3+3] cyclization-olefin-metathesis’ strategy. 相似文献
2.
The TiCl4-mediated [3+3] cyclization of 2,4-bis(trimethylsilyloxy)penta-1,3-diene with 3-silyloxyalk-2-en-1-ones afforded 2-acetylphenols, which were transformed into functionalized chromones. The Me3SiOTf-mediated condensation of the latter with 1,3-bis(silyl enol ethers) and subsequent domino ‘retro-Michael-aldol-lactonization’ reaction afforded 7-hydroxy-6H-benzo[c]chromen-6-ones. 相似文献
3.
Zafar Ahmed 《Tetrahedron》2005,61(8):2055-2063
A number of pulvinic acid natural products were prepared based on Suzuki cross coupling reactions of α-hydroxy-γ-alkylidenebutenolides which are readily available by cyclization of 1,3-bis-silyl enol ethers with oxalyl chloride. The formal total synthesis of pulvinic acid, atromentic acid, gomphidic acid and of 4-hydroxypulvinic acid, 4′-hydroxypulvinic acid and iso-gomphidic acid are reported. In addition, total syntheses of pinastric acid, xerocomic acid and variegatic acid were accomplished. 相似文献
4.
Functionalized fluorenones were prepared by sequential ‘[3+3] cyclization-Suzuki cross-coupling/Friedel-Crafts acylation’ reactions. 相似文献
5.
Van Thi Hong Nguyen 《Tetrahedron letters》2005,46(6):1013-1015
Functionalized dibenzo[b,d]pyran-6-ones were prepared by sequential ‘[3+3] cyclization-Suzuki cross-coupling’ reactions. 相似文献
6.
Functionalized triarylmethanes are prepared in two steps by FeCl3-catalyzed benzylation of acetylacetone to give 3-(diarylmethyl)pentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. 相似文献
7.
Sterically encumbered biaryls are prepared in two steps by CuI-proline-catalyzed arylation of acetylacetone to give 3-arylpentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. 相似文献
8.
Ihsan Ullah Rasheed Ahmad Khera Muhammad Nawaz Inam Iqbal Alexander Villinger Peter Langer 《Tetrahedron》2010,66(21):3824-3835
Sterically encumbered biaryls are prepared in two steps by combination of the CuI-proline-catalyzed arylation of acetylacetone with formal [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-dienes. In addition, the synthesis of 4,6- and 5,6-diarylsalicylates based on [3+3] cyclizations is reported. 相似文献
9.
Functionalized chromanes were prepared by sequential ‘[3+3]-cyclization/Williamson’ reactions of 1,3-bis(trimethylsilyloxy)-7-chlorohepta-1,3-dienes with 1,1,3,3-tetramethoxypropane, 3-silyloxyalk-2-en-1-ones, and 1,1-diacetylcyclopropane. The first step of the sequence involves [3+3] cyclizations of the starting materials to give 2-(3-chloropropyl)phenols. The subsequent cyclization proceeds by intramolecular nucleophilic substitution. 6-(2-Hydroxybenzoyl)chromanes were prepared based on sequential ‘[3+3]-cyclization/Williamson’ reactions of 1,3-bis(trimethylsilyloxy)-7-chlorohepta-1,3-dienes with 3-formylchromones. 相似文献
10.
The [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 1-hydroxy-5-silyloxy-4-en-3-ones afforded 6-(2-aryl-2-chloroethyl)salicylates, which were transformed into 3-aryl-3,4-dihydroisocoumarins by silica gel-mediated lactonization. 相似文献
11.
Muhammad Sher Zafar Ahmed Muhammad A. Rashid Anke Spannenberg Peter Langer 《Tetrahedron》2007,63(23):4929-4936
Functionalized and sterically encumbered diaryl ethers were prepared by [3+3] cyclization of 1,3-bis(silyl enol ethers) with 2-aryloxy-3-(silyloxy)alk-2-en-1-ones. 相似文献
12.
Rasheed Ahmad Khera Rasheed Ahmad Nguyen Thai Hung Alexander Villinger Peter Langer 《Tetrahedron》2010,66(9):1643-1652
Functionalized triarylmethanes are prepared in two steps by FeCl3-catalyzed benzylation of acetylacetone to give 3-(diarylmethyl)pentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. 相似文献
13.
2-(Phenylthio)benzoates containing a remote halide function are regioselectively prepared by ‘[3+3] cyclization/homo-Michael’ reactions of 1-methoxy-1-trimethylsilyloxy-3-phenylthio-1,3-butadienes with 1,1-diacylcyclopropanes. 相似文献
14.
Gerson Mroß 《Tetrahedron letters》2006,47(48):8519-8521
Functionalized diaryl ethers were prepared by [3+3] cyclization of 3-aryloxy-1-siloxy-1,3-butadienes with 3-(silyloxy)alk-2-en-1-ones. 相似文献
15.
Jennifer Hefner 《Tetrahedron letters》2008,49(14):2262-2264
Functionalized diaryl-diazenes (azo-dyes) were regioselectively prepared by formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 2-aryldiazenyl-3-silyloxy-2-en-1-ones. 相似文献
16.
Rüdiger Dede 《Tetrahedron letters》2004,45(50):9177-9179
The TiCl4 mediated cyclization of 1,3-bis-silyl enol ethers with 2-acetyl-1-silyloxybut-1-en-3-one and 3-acetyl-4-silyloxypent-3-en-2-one, readily prepared from 3-formyl(acetylacetone) and triacetylmethane, afforded a variety of functionalized acetophenones. 相似文献
17.
3-Hydroxyphthalates and 4-hydroxyisophthalates were prepared by sequential [3+3] cyclization reactions of 1,3-bis(silyl enol ethers) with 2- and 3-alkoxycarbonyl-3-(silyloxy)alk-2-en-1-ones. 相似文献
18.
6-Alkylidene-2,3-benzo-1,4-diaza-7-oxabicyclo[4.3.0]non-2-enes were prepared by cyclization of 1,3-bis(silyl enol ethers) with quinoxaline. 相似文献
19.
Functionalized 4-nitro- and 4-aminophenols were regioselectively prepared based on [3+3] cyclizations of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-ethoxy-2-nitro-2-en-1-ones. 相似文献
20.
Functionalized aryl fluorides were regioselectively prepared by [3+3] cyclization of 1,3-bis(silyl enol ethers) with 2-fluoro-3-silyloxy-2-en-1-ones. 相似文献