33414-84-5Relevant academic research and scientific papers
Palladium(II)/Lewis acid cocatalyzed oxidative annulation of 2-alkenylanilines and propargylic esters: An access to benzo[ b]azepines
Qiao, Hong,Zhang, Shengjun,Li, Kangkang,Cao, Zhengqiang,Zeng, Fanlong
, p. 10843 - 10851 (2019/09/12)
An attractive approach to valuable yet synthetically challenging benzo[b]azepines was established via palladium(II)/Lewis acid cocatalyzed oxidative [5 + 2] annulation of readily available 2-alkenylanilines and propargylic esters. The protocol features mild reaction conditions and good functional group tolerance, constituting an array of benzo[b]azepines in yields of 30-75%.
Neighboring Carbonyl Group Assisted Hydration of Unsymmetrical Aryl Alkynes Overriding Regular Selectivity
Mendhekar, Kishor L.,Pradhan, Tapas R.,Mallampudi, N. Arjunreddy,Mohapatra, Debendra K.
, p. 5787 - 5797 (2019/08/21)
A mild and highly regioselective gold-catalyzed hydration of γ-acetoxy aryl alkynes leading to anti-Markovnikov products by the assistance of a neighboring carbonyl group is presented. The reaction procedure operates under room temperature conditions with
Domino gold-catalyzed rearrangement and fluorination of propargyl acetates
De Haro, Teresa,Nevado, Cristina
supporting information; experimental part, p. 248 - 249 (2011/02/23)
A combination of IPrAuNTf2 as catalyst in the presence of Selectfluor has been successfully used for the high yielding synthesis of α-fluoroenones via 1,3-acyloxy rearrangement of propargyl acetates followed by Csp2-F bond formation,
Gold-catalyzed diastereoselective synthesis of α-fluoroenones from propargyl acetates
Hopkinson, Matthew N.,Giuffredi, Guy T.,Gee, Antony D.,Gouverneur, Véronique
supporting information; experimental part, p. 2737 - 2742 (2010/12/25)
A diastereoselective preparation of -fluoroenones from propargyl acetates has been developed proceeding via a gold-catalyzed rearrangement-fluorination cascade. Control reactions are consistent with a mechanism involving a gold-mediated 3,3-sigmatropic shift followed by a direct, nongold-catalyzed electrophilic fluorination of the allenyl acetate intermediate.
Gold-catalyzed efficient preparation of linear α-haloenones from propargylic acetates
Yu, Meng,Zhang, Guozhu,Zhang, Liming
experimental part, p. 1846 - 1855 (2009/07/04)
Versatile linear α-iodo- and α-bromoenones are prepared efficiently from readily accessible propargylic acetates using 2 mol % of Au(PPh3)NTf2. This reaction is easy to execute and has broad substrate scope. Good to excellent Z-selectivities are observed in the cases of propargylic acetates derived from aliphatic aldehydes.
Gold-catalyzed efficient preparation of linear α-lodoenones from propargylic acetates
Yu, Meng,Zhang, Guozhu,Zhang, Liming
, p. 2147 - 2150 (2008/02/03)
Only 2 mol % of Au(PPh3)NTf2 is needed to convert readily accessible propargylic acetates into versatile linear α-iodoenones in good to excellent yields. This reaction is easy to execute and has broad substrate scope. Good to excellent Z-selectivities are observed in the cases of aliphatic propargylic acetates derived from aldehydes.
Lewis acid catalyzed acylation reactions: Scope and limitations
Chandra, Kusum L,Saravanan,Singh, Rajesh K,Singh, Vinod K
, p. 1369 - 1374 (2007/10/03)
Acylation of alcohols, thiols, and sugars were studied with a variety of Lewis acids, and it was found that Cu- and Sn(OTf)2 are very efficient in catalyzing the reaction under mild conditions. Among these two catalysts, Cu(OTf)2 was preferred because of its lower cost and relatively higher yield of the acylated product. The reaction was studied in several solvents, but CH2Cl2 was preferred. It was also observed that the present method is suitable for acylation of tertiary alcohols. Sugars were also acylated without any epimerization at the anomeric center. It is further shown here that this method is also suitable for selective acylation of primary or secondary alcohols over tertiary ones.
Highly powerful and practical acylation of alcohols with acid anhydride catalyzed by Bi(OTf)3
Orita,Tanahashi,Kakuda,Otera
, p. 8926 - 8934 (2007/10/03)
Bi(OTf)3-catalyzed acylation of alcohols with acid anhydride was evaluated in comparison with other acylation methods. The Bi(OTf)3/acid anhydride protocol was so powerful that sterically demanding or tertiary alcohols could be acylated smoothly. Less reactive acylation reagents such as benzoic and pivalic anhydride are also activated by this catalysis. In these cases, a new technology was developed in order to overcome difficulty in separation of the acylated product from the remaining acylating reagent: methanolysis of the unreacted anhydride into easily separable methyl ester realized quite easy separation of the desired acylation product. The Bi(OTf)3/acid anhydride protocol was applicable to a wide spectrum of alcohols bearing various functionalities. Acid-labile THP- or TBS-protected alcohol, furfuryl alcohol, and geraniol could be acylated as well as base-labile alcohols. Even acylation of functionalized tertiary alcohols was effected at room temperature.
Highly efficient and versatile acylation of alcohols with Bi(OTf)3 as catalyst
Orita, Akihiro,Tanahashi, Chiaki,Kakuda, Atsushi,Otera, Junzo
, p. 2877 - 2879 (2007/10/03)
A very convenient route for the acylation of alcohols is provide by using a Bi(OTf)3 catalyst [Eq. (1)]. In this protocol hindered and functionalized alcohols are acylated at 25°C, and solvents can be employed without purification. R= primary, secondary, tertiary alkyl, aryl; R'=Me, Ph, tBu.
