I am conducting an Aldol formation reaction in water, and below is the experimental protocol I am following (from J. Org. Chem. 1994, 59, 3590—3596):

Formation of Aldol in Water using Yb(OTf)3 Catalyst

To commercial formaldehyde solution ($\pu{1 mL}$) and THF ($\pu{3 mL}$) were successively added $\ce{Yb(OTf)3}$ ($\pu{0.04 mmol}$, $\pu{10 mol\%}$) and silyl enol ether 1-(Trimethylsiloxy)cyclohexene ($\pu{0.4 mmol}$) in THF ($\pu{1 mL}$) at rt. The mixture was stirred for $\pu{24 h}$ at this temperature and then THF was removed under reduced pressure. Water was added and the product was extracted with dichloromethane. After the usual workup, the crude product was chromatographed on silica gel to give the pure adduct.

Despite multiple attempts, I was unable to get the aldol product. The procedure itself is not even that convoluted to follow. NMR shows bare starting materials. Can anyone please help me to troubleshoot my issue?

Post edit: JOC reference as follows:

S. Kobayashi, I. Hachiya, “Lanthanide Triflates as Water-Tolerant Lewis Acids. Activation of Commercial Formaldehyde Solution and Use in the Aldol Reaction of Silyl Enol Ethers with Aldehydes in Aqueous Media,” J. Org. Chem. 1994, 59(13), 3590–3596 (DOI: 10.1021/jo00092a017).

  • 1
    $\begingroup$ Your JOC reference is a link to a paper on a different topic in Tetrahedron. $\endgroup$
    – Zhe
    May 16 '19 at 13:30
  • $\begingroup$ Also, we have no idea what the reference enolate is or what your enolate is. Depending on what the identities of these substances are, there's no reason for it to work a priori. $\endgroup$
    – Zhe
    May 16 '19 at 13:32
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    $\begingroup$ @Zhe: I put the info about JOC paper for your convenience. $\endgroup$ May 16 '19 at 18:26
  • $\begingroup$ @chemrese: You have described the procedure for hydroxymethylation of O-silyl enolates (ethers). If you are using other aldehydes other than formaldehyde, there is an other procedure. Thus, it's better to described one of your failed attempts so that we have a clear picture. $\endgroup$ May 16 '19 at 19:56
  • $\begingroup$ @Zhe fixed it. The silyl enol ether I've used is: 1-(Trimethylsiloxy)cyclohexene $\endgroup$
    – chemrese
    May 17 '19 at 2:40

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