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Triflimide (HNTf2)–catalyzed aldehyde cross-aldol reaction using “super silyl” enol ethers

Abstract

The synthesis of the acetaldehyde-derived tris(trimethylsilyl)silyl (super silyl) enol ether is described, as well as its use in the high-yielding aldehyde cross-aldol reaction. The super silyl enol ether shows unprecedented reactivity in giving the 1:1 adduct in very high yield. This reaction is catalyzed by 0.05 mol% of the Brønsted acid triflimide (HNTf2) and is complete within 15 min, making the protocol very attractive for large-scale synthesis.

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Correspondence to Hisashi Yamamoto.

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Boxer, M., Yamamoto, H. Triflimide (HNTf2)–catalyzed aldehyde cross-aldol reaction using “super silyl” enol ethers. Nat Protoc 1, 2434–2438 (2006). https://doi.org/10.1038/nprot.2006.389

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