Aldol Reaction in Water Not Working

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](https://pubs.acs.org/doi/abs/10.1021/jo00092a017?journalCode=joceah)):



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


