Convert the following and show a Mechanism

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It has to be just in a single step and on the arrow head you can't use multiple reagents altogether. Can anyone do it? I am unable to do it in a single step.

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This is my attempt ..! But it is multistep, one step is required ..!

  • $\begingroup$ This looks like a honework question. Please show us your attempt towards answering the question. $\endgroup$ – getafix Sep 18 '16 at 6:34
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    $\begingroup$ Singlet oxygen does the trick, if I am not wrong. As far as I can tell, I believe that with typical A-level reagents this conversion is impossible in one step. $\endgroup$ – orthocresol Sep 18 '16 at 6:43
  • $\begingroup$ What is A level reagent ? $\endgroup$ – Chloritone_360 Sep 18 '16 at 6:45
  • $\begingroup$ Reagents taught in the A level syllabus. $\endgroup$ – orthocresol Sep 18 '16 at 6:48
  • $\begingroup$ Singlet oxygen conversion: chem.wisc.edu/areas/reich/chem547/2-redox%7B26%7D.htm Articles with this specific reaction: 1 (tBuOOH, some weird catalyst), 2 (O2, Au nanoparticles), 3 (O2, rose bengal, PPh3) $\endgroup$ – orthocresol Sep 18 '16 at 6:56

You're supposed to turn an alkene into an an allylic alcohol in one step. The "classical" reagent for this conversion is selenium dioxide, $\ce{SeO2}$. Have a look at some older references, such as J. Org. Chem., 1979, 44, 4683-4689. DOI

As kindly pointed out by orthocresol, this elegant method will unfortunately furnish the the wrong allylic alcohol. Whether in situ isomerization is possible (allylic hydroxylation in acidic medium) is feasible can't be decided until I have another coffee ;)

(Please note that a procedure using singlet oxygen will need two steps: the Schenck ene reaction furnishes a hydroperoxide which you would have to reduce.)

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    $\begingroup$ I was under the impression that SeO2 oxidation didn't proceed with transposition of the double bond $\endgroup$ – orthocresol Sep 18 '16 at 7:35
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    $\begingroup$ @orthocresol You are right and I definitely need another coffee this mormning ;-) $\endgroup$ – Klaus-Dieter Warzecha Sep 18 '16 at 7:52
  • $\begingroup$ There is a paper which used $\ce{SeO2 + Ac2O}$ ("und Verseifen des erhaltenen Acetats") but it's old and Reaxys won't let me access it. Guillemonat, Annales de Chimie (Cachan, France), 1939, vol. <11> 11, p. 143, 188, 191, 193, 194, 196; Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences, 1938, vol. 206, p. 1126 $\endgroup$ – orthocresol Sep 18 '16 at 8:33
  • $\begingroup$ youtu.be/m51VmzjUGRA found this one . Many things about SeO2 though it is in Hindi $\endgroup$ – Chloritone_360 Sep 28 '16 at 6:14

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