191403-25-5Relevant academic research and scientific papers
Vanadium(V)-mediated rearrangement/halogenation cascade: Synthesis of α-haloenones from propargyl alcohols
Zhao, Meng,Mohr, Justin T.
, p. 4115 - 4124 (2017/06/29)
A method is described for the oxidative Meyer–Schuster-type rearrangement of propargylic alcohols to (Z)-α-chloro- and α-iodoenones using VOCl3 as a multifunctional reagent. The vanadium reagent is found to serve as rearrangement promoter as well as an active chlorenium ion donor. Yields are improved when VOCl3 is employed in conjunction with N-halosuccinimide reagents, giving some insights into the complex mechanism.
Cadmium(II) Chloride-Catalyzed Dehydrative C?P Coupling of Propargyl Alcohols with Diarylphosphine Oxides to Afford Allenylphosphine Oxides
Yang, Jianlin,Zhang, Ming,Qiu, Kang,Wang, Lize,Yu, Jingjing,Xia, Zefeng,Shen, Ruwei,Han, Li-Biao
supporting information, p. 4417 - 4426 (2017/12/26)
The cadmium(II) chloride-catalyzed dehydrative C?P cross-coupling reaction of propargyl alcohols with diarylphosphine oxides is reported. Several propargyl alcohols including those bearing the sterically demanding tert-butyl group at the triple bond terminus can be used as good substrates in the reaction to produce the corresponding allenylphosphine oxides in good to high yields in acetonitrile at 100 °C. The reaction can also be easily scaled up to a gram-scale synthesis. A mechanism study indicates that the reaction may proceed through a process of propargylic substitution to generate phosphonite intermediates followed by [2,3] sigmatropic rearrangement to produce the allenyl products, rather than through a common allenylative substitution resulting from P-nucleophilicity. (Figure presented.).
Synthesis of Vinyl-, Allyl-, and 2-Boryl Allylboronates via a Highly Selective Copper-Catalyzed Borylation of Propargylic Alcohols
Mao, Lujia,Bertermann, Rüdiger,Emmert, Katharina,Szabó, Kálmán J.,Marder, Todd B.
supporting information, p. 6586 - 6589 (2017/12/26)
An efficient methodology for the synthesis of vinyl-, allyl-, and (E)-2-boryl allylboronates from propargylic alcohols via Cu-catalyzed borylation under mild conditions is reported. In the presence of commercially available Cu(OAc)2 or Cu(acac)2 and Xantphos, the reaction affords the desired products in up to 92% yield with a broad substrate scope (43 examples). Isolation of an allenyl boronate as the reaction intermediate suggests that an insertion-elimination-type reaction, followed by borylcupration, is involved in the borylation of propargylic alcohols.
Gold(I)-Catalyzed Synthesis of Tetrahydrocarbazoles via Cascade [3,3]-Propargylic Rearrangement/[4+2] Cycloaddition of Vinylindoles and Propargylic Esters
Pirovano, Valentina,Arpini, Elisa,Dell'acqua, Monica,Vicente, Rubén,Abbiati, Giorgio,Rossi, Elisabetta
supporting information, p. 403 - 409 (2016/02/12)
A gold(I)-catalyzed cascade [3,3]-propargylic rearrangement and [4+2] cycloaddition reaction of 2-vinylindoles with propargylic esters is reported. The reaction leads to the synthesis of highly substituted tetrahydrocarbazole derivatives in high yields and diasteroselectivities. Furthermore, a preliminary screening for an asymmetric version of this reaction is described.
Dehydrogenative Meyer-Schuster-like rearrangement: A gold-catalyzed reaction generating an alkyne
Yu, Yang,Yang, Weibo,Pflaesterer, Daniel,Hashmi, A. Stephen K.
supporting information, p. 1144 - 1147 (2014/03/21)
Easily accessible propargylic esters are converted to the inverted alkynyl ketones in an oxidative gold-catalyzed reaction. Gagosz's catalyst in combination with PhI(OAc)2 is the best system for this conversion and 18 examples with yields up to 80 % are reported. The results indicate that the triple bond in the product is formed by elimination from a vinylgold intermediate. In a formal sense the new conversion overall is a dehydrogenative Meyer-Schuster rearrangement. It takes alkynes: Propargyl esters can be converted into alkynyl ketones by a new oxidative gold-catalyzed reaction. The best catalyst system is Ph3PAuCl/AgNTf2 in combination with the oxidant PhI(OAc)2. The yields are as high as 80 % and the reaction can be conducted in the presence of air. Copyright
Highly diastereoselective synthesis of cyclopentenones via a one-pot gold catalysis, Nazarov cyclization and alkylation cascade
Liu, Meng-Qi,Zhou, Ai-Hua,Jiang, Shuang,Wang, Jia-Qi,Ye, Long-Wu
supporting information, p. 2161 - 2167 (2014/08/18)
Starting from readily available propargylic carboxylates, three sequential transformations [gold-catalyzed tandem reaction, scandium(III) trifluoromethanesulfonate catalyzed Nazarov cyclization, alkylation reaction] in a one-pot process led to the formation of cyclopentenone derivatives in excellent diastereoselectivities and moderate to good overall yields. Georg Thieme Verlag Stuttgart. New York.
Gold meets rhodium: Tandem one-pot synthesis of β-disubstituted ketones via meyer-schuster rearrangement and asymmetric 1,4-addition
Hansmann, Max M.,Hashmi, A. Stephen K.,Lautens, Mark
supporting information, p. 3226 - 3229 (2013/07/26)
An asymmetric one-pot tandem Au/Rh-catalyzed synthesis of highly enantioenriched β-disubstituted ketones starting from racemic propargyl alcohols is disclosed. The compatibility of the two metal complexes (Au/Rh) and their orthogonal ligand systems (NHC/d
Condensation of propargylic alcohols with N-methylcarbazole and carbazole in [bmim]PF6 ionic liquid; Synthesis of novel dipropargylic carbazoles using TfOH or Bi(NO3)3·5H2O as catalyst
Kumar, G.G.K.S. Narayana,Laali, Kenneth K.
, p. 965 - 969 (2013/03/13)
A series of doubly-propargylated N-methylcarbazole and carbazole derivatives were synthesized in good to excellent isolated yields in (bmim)PF6 using triflic acid (10 mol %). The use of bismuth nitrate (20 mol %) instead of triflic acid allowed stepwise propargylation employing two different propargylic alcohols, to prepare mixed bis-propargylated carbazoles. Simple product isolation, mild reaction conditions, and repeated recycling and reuse of (bmim)PF6 are added advantages of this IL-mediated synthetic method.
Gold- and silver-catalyzed reactions of propargylic alcohols in the presence of protic additives
Pennell, Matthew N.,Turner, Peter G.,Sheppard, Tom D.
supporting information; experimental part, 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.
Iron-catalyzed C-O bond activation for the synthesis of propargyl-1,2,3-triazoles and 1,1-bis-triazoles
Yan, Wuming,Wang, Qiaoyi,Chen, Yunfeng,Petersen, Jeffrey L.,Shi, Xiaodong
supporting information; experimental part, p. 3308 - 3311 (2010/10/19)
(Equation Presented). The FeCl3-catalyzed triazole propargylation was developed. This transformation was suitable for a large scope of substituted propargyl alcohols, giving the corresponding propargyl triazoles in excellent yields (up to 96%). Further derivatization produced the 1,1-bis-triazoles in excellent yields and regioselectivity, which could be applied as potential transition metal ligands or new reagents.
