56188-07-9Relevant articles and documents
Complementary iron(II)-catalyzed oxidative transformations of allenes with different oxidants
Sabbasani, Venkata R.,Lee, Hyunjin,Xia, Yuanzhi,Lee, Daesung
supporting information, p. 1151 - 1155 (2016/01/20)
Substituent- and oxidant-dependent transformations of allenes are described. Given the profound influence of the substituent on the reactivity of allenes, the subtle differences in allene structures are manifested in the formation of diverse products when reacted with different electrophiles/oxidants. In general, reactions of nonsilylated allenes involve an allylic cation intermediate by forming a C-O bond, at the sp-hybridized C2, with either DDQ (2,3-dichloro-5,6-dicyano-p-benzoquinone) or TBHP (tert-butyl hydroperoxide), along with FeCl2·4 H2O (10 mol %). In contrast, silylated allenes favor the formation of propargylic cation intermediates by transferring the allenic hydride to the oxidant, thus generating 1,3-enynes (E1 product) or propargylic THBP ethers (SN1 product). The formation of these different putative cationic intermediates from nonsilylated and silylated allenes is strongly supported by DFT calculations. Profound impact: Iron(II)-catalyzed transformations of allenes induced by either DDQ or tBuOOH depend on the substituent on the allenes. Nonsilylated and silylated allenes show complementary reactivity upon exposure to DDQ and tBuOOH in the presence of an iron(II) catalyst. Nonsilylated allenes incorporate the oxidant at the sp-hybridized carbon, whereas the silylated allenes generate 1,4-dehydrogenated 1,3-enynes. DDQ=2,3-dichloro-5,6-dicyano-1,4-benzoquinone.
Synthesis of functionalized resorcinols by rhodium-catalyzed [5+1] cycloaddition reaction of 3-acyloxy-1,4-enynes with CO
Brancour, Celia,Fukuyama, Takahide,Ohta, Yuko,Ryu, Ilhyong,Dhimane, Anne-Lise,Fensterbank, Louis,Malacria, Max
supporting information; experimental part, p. 5470 - 5472 (2010/09/18)
A novel [5+1] type carbonylative cycloaddition reaction has been developed using a Rh complex as catalyst. This reaction can convert readily available 3-acyloxy-1,4-enynes and CO to a wide range of functionalized resorcinols in good yields. A mechanism involving Rh-catalyzed cyclocarbonylation of 3-acyloxy-1,4-enynes accompanied by a 1,2-acyloxy shift is proposed for the present [5+1] type cycloaddition reaction. The Royal Society of Chemistry 2010.
