Flash vacuum pyrolysis of 1,6-diphenyl-1,5-hexadien-3-ynes: tandem diaryldienyne cyclizations to form chrysene
作者:Motohiro Sonoda、Kayo Itahashi、Yoshito Tobe
DOI:10.1016/s0040-4039(02)01062-6
日期:2002.7
Flashvacuumpyrolysis of 1,6-diphenyl-1,5-hexadien-3-yne at 1000°C and its bromo derivative at 800°C yielded chrysene as the major product through tandem diaryldienyne cyclizations.
Sonogashira Cross-Coupling Reactions
and Construction of the Indole Ring System Using a Robust, Silica-Supported
Palladium Catalyst
作者:Elizabeth Tyrrell、Leon Whiteman、Neil Williams
DOI:10.1055/s-0028-1083375
日期:——
The use of a recyclable silica-supported palladium catalyst in Sonogashira couplings and indole syntheses using a range of functionalised substrates is described. The catalyst is shown to be both robust and versatile, effecting the synthesis of 2-phenylindole in quantitative yield without the need for N-protection, a copper cocatalyst, a base, or a solvent.
Addition and Cyclization Reactions in the Thermal Conversion of Hydrocarbons with an Enyne Structure, 4. Formation and Rearrangements of Bicyclic C10H8 Aromatics from 1-Phenyl-1-buten-3-yne
作者:Kathrin Schulz、Jörg Hofmann、Gerhard Zimmermann
DOI:10.1002/jlac.199719971217
日期:1997.12
The thermal conversion of 1-phenyl-1-buten-3-yne (1) into the cycloisomerization products naphthalene (2), azulene (3), and 1-methylene-1H-indene (4) has been studied at temperatures between 550 and 1000°C, a reaction time of approximately 0.3 s at 13 Torr (FVP) and at low partial pressures in a quartz flow system. The results obtained by FVP as well as in the presence of chemically modified diluent
Addition and Cyclization Reactions in the Thermal Conversion of Hydrocarbons with an Enyne Structure, 5. High-Temperature Ring Closures of 1,3-Hexadien-5-ynes to Naphthalenes – Competing Reactions via Isoaromatics, Alkenylidene Carbenes, and Vinyl-type Radicals
2-ethynylstyrenes 7a–c were subjected to high-temperature pyrolysis. The cycloisomerization products isolated suggest that these are formed by three competing processes: by (i) an electrocyclic or a molecule-induced, (ii) an alkenylidenecarbene controlled, and (iii) a radical-controlled ring-closure process. To estimate the relative importance of these three reactions here mentioned, the substrates have
Highly Enantioselective Alkynylation of Trifluoropyruvate with Alkynylsilanes Catalyzed by the BINAP−Pd Complex: Access to α-Trifluoromethyl-Substituted Tertiary Alcohols
作者:Kohsuke Aikawa、Yu̅ta Hioki、Koichi Mikami
DOI:10.1021/ol102541s
日期:2010.12.17
A highlyenantioselective alkynylation catalyzed by the dicationic (S)-BINAP−Pd complex with a variety of alkynylsilanes and trifluoropyruvate is described. The catalytic reaction is applicable to highlyenantioselective addition of polyyne to trifluoropyruvate to construct α-trifluoromethyl-substituted tertiaryalcohols as enantiomerically enriched forms. The alkynyl products can be converted into