90831-80-4Relevant academic research and scientific papers
Reagent Control Enables Selective and Regiodivergent Opening of Unsymmetrical Phenonium Ions
Xu, Shiyan,Holst, Hannah M.,McGuire, Shelby B.,Race, Nicholas J.
, p. 8090 - 8096 (2020)
We report the first examples of selective and regiodivergent opening of unsymmetrical phenonium ions with chloride ions. These reactions are enabled by the dual role of SnCl4 and TiCl4 as Lewis acids and chloride nucleophiles. Reagen
Gold- and silver-catalyzed reactions of propargylic alcohols in the presence of protic additives
Pennell, Matthew N.,Turner, Peter G.,Sheppard, Tom D.
scheme or table, p. 4748 - 4758 (2012/05/04)
A wide range of primary, secondary and tertiary propargylic alcohols undergo a Meyer-Schuster rearrangement to give enones at room temperature in the presence of a gold(I) catalyst and small quantities of MeOH or 4-methoxyphenylboronic acid. The syntheses of the enone natural products isoegomaketone and daphenone were achieved using this reaction as the key step. The rearrangement of primary propargylic alcohols can readily be combined in a one-pot procedure with the addition of a nucleophile to the resulting terminal enone, to give β-aryl, β-alkoxy, β-amino or β-sulfido ketones. Propargylic alcohols bearing an adjacent electron-rich aryl group can also undergo silver-catalyzed substitution of the alcohol with oxygen, nitrogen and carbon nucleophiles. This latter reaction was initially observed with a batch of gold catalyst that was probably contaminated with small quantities of silver salt.
A general procedure for the synthesis of enones via gold-catalyzed Meyer-Schuster rearrangement of propargylic alcohols at room temperature
Pennell, Matthew N.,Unthank, Matthew G.,Turner, Peter,Sheppard, Tom D.
supporting information; experimental part, p. 1479 - 1482 (2011/04/26)
Meyer-Schuster rearrangements of propargylic alcohols take place readily at room temperature in toluene with 1-2 mol % PPh3AuNTf2, in the presence of 0.2 equiv of 4-methoxyphenylboronic acid or 1 equiv of methanol. Good to excellent yields of enones can be obtained from secondary and tertiary alcohols, with high selectivity for the E-alkene in most cases. A one-pot procedure for the conversion of primary propargylic alcohols into β-arylketones was also developed, via Meyer-Schuster rearrangement followed by Pd-catalayzed addition of a boronic acid.(Figure Presented)
Heck reactions of aryl bromides with alk-1-en-3-ol derivatives catalysed by a tetraphosphine/palladium complex
Berthiol, Florian,Doucet, Henri,Santelli, Maurice
, p. 5633 - 5636 (2007/10/03)
cis,cis,cis-1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane/ [PdCl(C3H5)]2 efficiently catalyses the Heck reaction of alk-1-en-3-ol with a variety of aryl bromides. In the presence of hex-1-en-3-ol or oct-1-en-3-ol, the β-arylated carbonyl compounds were selectively obtained. Linalool and 2-methylbut-3-en-2-ol led to the corresponding 1-arylalk-1-en-3-ol derivatives. Turnover numbers up to 69,000 can be obtained for this reaction. A minor electronic effect of the substituents of the aryl bromide was observed. Similar reaction rates were observed in the presence of activated aryl bromides such as bromoacetophenone and deactivated aryl bromides such as bromoanisole.
REDUCTION OF BENZYLIDENEACETONE DERIVATIVES WITH Pd/SiO2-AlPO4 AS CATALYST AND CYCLOHEXENE AS HYDROGEN DONOR
Alba, A.,Aramendia, A.,Borau, V.,Garcia-Raso, A.,Jimenez, C.,Marinas, J. M.
, p. 917 - 921 (2007/10/02)
The hydrogen transfer reduction of benzylidenacetone derivatives p-X-C6H4-CH=CH-CO-R (X=-OCH3, H; R=C6H5, alkyl, OR, OH) using cyclohexene as hydrogen donor has been studied.The selective reduction of the C=C bond is observed and the effects of the nature of X and R, solvent, catalyst, and reaction temperature on the initial reaction rate are analyzed.In all cases, and for any substrate or catalyst, the reaction is firts-order with respect to the hydrogen donor and acceptor.
