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Please login to access the full content or check if you have access via Variation 1: Of Ketones

DOI: 10.1055/sos-SD-026-00532

Landais, Y.; Vincent, J. M.Science of Synthesis, (200526673.

One of the most frequently used reagents for the direct introduction of a ketone group α to a carbonyl group is selenium dioxide and it generally affords 1,2-diketones in fair to good yields by simply refluxing the reactants in ethanol or 1,4-dioxane.[‌104‌] Refluxing cycloheptanone 130 in ethanol for 6hours with selenium dioxide (1 equiv) affords cycloheptane-1,2-dione (131) in 91% yield (Scheme 31).[‌105‌] Selenium dioxide oxidations probably occur through a β-oxo seleninic acid organoselenium intermediate, formed by the electrophilic attack of selenious acid on the enol, which after Pummerer-like decomposition yields the diketone.[‌106‌]

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Meeeeee, eee eee ee eeeeeeee eeeeeee eee eeeee eeeeeeeee, eeeeeeeeee eeeeeeee ee eeeeeeee eeeeeee eee eeeeeeee ee eeeeeeeeeee eeee eeeee eee eeeeeeeee eee eeeeee, eeee eeeeeeeeeee eeeeee eeeeeeeeeee eee eeeeeeeeee eeeeee ee eeeeeee, eee eeeeeeeeee ee eeeeeeee eee eeeee eeeeeeee-eeeeeeeeee eeeeeeeeeeee eeee eeeeeeeeee eeeeeeeee eee eeeeeeee,[‌888‌] eee eee eeeee eeeeeeee eeeeeeeeee eeeeeeee eeee eeeeee ee eeeeeee eeeeeeeee ee eeee eeeeeeeee. Meee ee eeeeeeeeeee ee eee eeeeeeeeeeeeee ee eeeeeeeeee 888 ee eeeee eeeeeeeee eeeeee ee M8 eee M88 eeeeeeeee eee 8-eeeeeee-88,88-eeeee, 88-eeeeeeeeeeee (888) (Meeeee 88).[‌888‌] Meeeeeeeeeee, eeee eeeeeeee ee eeeeeeeeee eeee ee eee eee eeeeeeeee eeee ee eee eeeeeeeee ee eeeeeeeeeeee eeeeee eeeeeee eeeeeeee eee eee eeee eeee ee eee eeeeeeeee ee eeeeeeeeee[‌888‌] eee eee eeeeeeeeee eeeeeeeee β-eeeeeeeeeee,[‌888‌] eeeee eeeeee.

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Me eeeeeeeee eee eeeeeee eeeeee eee eee eeeeee eeeeeeeee ee 8,8-eeeeeeeee eeee eeeeeeeeeee eeeeeeee, ee eee eeeee eeee, eee eeeeeeeeee ee eee eeeeeeee eeeeee eeee eee eeeeeeeeeeeee eeeeeee eeeeeeee eeeeeeeeee eeeee eeee-eeeeeeeee(eeeeeeeeeeeee)eeeeeee (Meeeeeeee'e eeeeeee),[‌888‌‌888‌] eeeeeeee ee eeeeeeeee eeeeeeee ee eee eeeeeee eeeeee eeee ee eeeeeee eeeeee (Meeeee 88).[‌888‌,‌888‌] Mee eeeeeeee eeeeee 888 eeeeee eeee eee eeeeeeeee eeeeeeeee eeeeeeee ee eeee eeeee, eeeeeeee eeeeee eeeeeeeeeeeeeeee ee eee eeeeeee eeeeee eeeeeee eeeeeee eeeeeeeee ee eee eeeeeeeeeeeee. Mee eeeeeeeeeeeeeeee ee eeeeeeeee ee eee eeeeeeeeeeee eeeee eeeeeeeeeeeeeeeeeeeeeeeeee (MMMM) ee eee eeeeeeeeeeeeeee. Meeee eeee eeeeeeeee, eeee- eee eeeee-eeeeeeeeeee eeeeeee 888 eee eeeeeeeee eeee 8,8-eeeeeeeee 888 ee eeee eeeeee (Meeeee 88).[‌888‌] Meeeeeeeeeeee, ee eeeeeeeee eee eeee eeeeeeee eeeeeee eeee(eeeeeeeeeeeee)eeeeeee,[‌888‌] eeee eeeeeeee eeeeee eee eeeeeeee eee eeeeeeeee eeee eee eeeeeeeeeeeee eeeeeee eeeeeee. Meeee eeeeeeeee, β-eeeee-α,β-eeeeeeeeeee eeeeee eeeeeeeeeee 888 eee eeeeeeee eeeeeeee ee eeeeeee eeeeee ee eeee eee eeeeeeeeeeeee α-eee eeeeee eee α-eee eeeeeeee.[‌888‌]

Meeeee 88 Meeeeeeee ee Meeeeeeeeee eeee eeee-Meeeeeeee(eeeeeeeeeeeee)eeeeeee[‌888‌]

Mee eeeeeeeee-eeeeeeee, eeeeeee-eeee eeeeeeeee ee α-eeeeeeeee eeeeeee ee 8,8-eeeeeeeee eeeeeeee eee eeeeeeee ee α-(8-eeeeeeeeeeeeeeeeeeeeee) eeeeee eeeeeeeeeeeee eeee eeeeeeee 8-eeeee.[‌888‌] α-(8-Meeeeeeeeeeeeeeeeeeeee) eeeeeee eee eeeeeeee ee eeeeeeee ee eeeeeee eeee [eeeeeee(8-eeeeeeeeeeeeeeeeeeeeee)eeee]eeeeeee eeeee eeeeeeeee eeeeeeeeeee (88eee) eee eeeee eeee eeeeeee eeeeeeeeeeee eeeeeeeee eeee eeeeeeee 8-eeeee ee eeee 8,8-eeeeeeeee ee eeee ee eeee eeeeee.

Mee eee eeee eeeeeeee 8,8-eeeeeeeeeee-8-eee eeeeeeeeeee (eeeeeeeeeeeee), eeeeeeee eeee ee M-eeeeeeeeeeeeeeee/eeeeeeee eeeeeeeee,[‌888‌] ee eeeeeeee eeeeeee/eeeeeeee eeeeeeeee,[‌888‌] eeeeee eee eeeeeee 8,8-eeeeeeeee ee eeeeeeeee eeeeee. Meeee eeeeeeeee eeeeeee eeee eeee eeeeeeee.[‌888‌]

Meeeeeeeeeee Meeeeeeee

Meeeeeeeeeee-8,8-eeeee (888); Meeeeee Meeeeeeee:[‌888‌]

MMMMMMM: Meeeeeee eeeeeee ee eeeee ee eeeeeeeeee eee eeeeeeeee.

M eeee ee eeeeeeeeeeeeee (888; 888e, 8.8eee) ee eee MeMM (888eM) eee eeeeee ee e 8-M eeeee eeeeee eeee e Meeeeee eeeeee, e eeeeee eeeeeeeee, eee e eeeeeeee eeeeee. M eeee ee eeeeeeee MeM8 (888e, 8.8eee) ee e eeeeeee ee eee MeMM (888eM) eee 88% MeMM (8888eM) eee eeeeee ee eee eeeeeeee eeeeee. Mee eeeeeeeeeeeeee/eeeeeee eeee eee eeeeeeee eee eee MeM8 eeee eee eeeee eeee e eeeeee ee 8.8e. Mee eeeeeeeee eeeeeee eee eeeeeeee eee ee eeeeeeeeee 8e, eeee eeeeeeee. Meeeee. 8M ee eeeeeee eee eeeeeeeee eeee eee eeeeeeee ee eeeeeeeeeee eeeeeeee; eee eeeeeee eee eeee eeeeeeee eeeee, eee eee eeeeeeeeeeee eeeeeeeee eeeee eeeeeee eeeeeeee. Mee eeeeeeee 888 eee eeeeeeee ee e eeee eeeeee eeeeee; eeeee: 888e (88%); ee 888888°M/88Meee.

8,8-Meeeeeeee 888; Meeeeee Meeeeeeee:[‌888‌]

M eeeeeee ee 888 (8eeee) eee eeee-eeeeeeeee(eeeeeeeeeeeee)eeeeeee (8.8e, 8.8eeee) eee eeeeee ee 88°M eeeee M8 eeee eeeeeeee eee 88e. Mee eeeeeeeee eeeeeee eee eeeeeeeee ee eee MM8Me8 (888eM) eeeeeeeeee eeeeeeeeeeeeeeeeeeeeeeeeee (8ee) eee eee eeee ­eeeeeeeeeeeeeee ee 88°M eeee e Meeeeeee MMM 888-M eeee eeeeeeee ee 88M ee eee eeeee eeeeee. Meeee eee eeeeee ee eeeeee eee eeeeee (8.8 eeeee ee M8, 88eee), eee eeeeeeeeeee eee eeeeeee eee eee eeeeeee eee eeeeeee ee eeee eeeeee ee ee. Meeeeeeeeee ee eee eeeeeee eeee e eeeee eee, eeeee eee eeeeeeeee ee Me8M, eeeeee eeeeeeeeee eeee M8M, eeeee (MeMM8), eee eeeeeeeee eeee eeeeeeeee eeeeeeee. Meeeeeeeee eeeeeee Meeeee eee eeeeeeeeeee eeee 888.