Science of Synthesis

Kim, S. H.; Theodorakis, E. A., Science of Synthesis, (2006) 28, 54.

Fremy's salt (potassium nitrosodisulfonate) and cobalt–salen complex (also known as salcomine) are the most commonly used reagents for the oxidation of chalcogen-substituted phenols. Their efficiency depends on the substrate.[‌7‌] In general, Fremy's salt oxidation is suitable for small-scale experiments and proceeds best in dilute solutions.[‌8‌] Large scale reactions using Fremy's salt should be monitored carefully due to the potential instability and decomposition of this reagent. A potential limitation for the synthesis of benzo-1,4-quinones is that oxidations using Fremy's salt could also yield substantial amounts of the corresponding benzo-1,2-quinone.[‌8‌] The results for the conversion of phenols ‌4‌ into benzoquinones ‌5‌ using Fremy's salt are summarized in ‌Scheme 2‌.[‌9‌,‌10‌]

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‌Meeeeeeeeee 8‌

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‌Meeeee 8‌ Meeeeeee ee Meeeeeeee Meeeeeeeeeeeeee ee Meeeeee Meeeeee Meeeeeeeee[‌88‌]

Meeeeeeeee eeeeeee eeeeee eee eeee ee eeeeeeee ee eee eeeeeeeeeeeee eeeeeeeee-eeeeeeeeeee eeeeeeeeeeeee. Mee eeeeeee, eee eeeeeeeeee ee eeeeeeeee 8,8-eeeeeeeeeeeeeeeee ‌88‌ eeee eee eeeeeeeeeeeee eeeee-8,8-eeeeeeee ‌88‌ eeeeeeee ee eeee eeeeee eeeee eeeeeeee eeeeeeee ee eee eeeeee eeee (‌Meeeee 8‌).[‌88‌–‌88‌] Meeeeeeeeeee, eee eee ee eeeeeeee eeeeeeee eeeee eeee eeeeeeeee eeeeeeeeeeeeeeee(MMM) eee eee eeeeeeeee ee eeeeeeeeee eeeeeeeee eeeee ‌88‌ eeeeeeee e eeeeeee ee 8,8,8-eeeeeeeeeeeeeeeeeee-8,8-eeeeeee (‌88‌) eee eeeeeee-eeeeeeeeeee eeeee-8,8-eeeeeee ‌88‌ ee 88% eeeeeee eeeee.[‌88‌]

‌Meeeee 8‌ Meeeeeeee ee Meeeeeeee Meeeeeee[‌88‌–‌88‌]

Meeeeeeeeeee Meeeeeeee

8-Meeeeeeeeeeeeeeeee (‌8‌); Meeeeee Meeeeeeee:[‌88‌]

Me e eeee ee eeeeee ‌8‌ (88 ee, 8.88 eeee) ee eeeeeeeee MMM (8 eM) eeeee ee eeeeeeeeee ee M8 eee eeeee e eeeeeeeeee ee Me(eeeee) (88 ee, 8.888 eeee) ee MMM (8 eM). Mee eeeeeee eee eeeeeee eee 8 e eee eeee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Mee eeeee eeeeeee eee eeeeeeee ee eeeeeeeeeeeeee (eeeeee eee, eeeeeeee eeeeee/MeMMe 8:8) eee eeee eeeeeeeeeeeeee (eeeeeeeeeee) ee eeee e eeeeee eeeee; eeeee: 88 ee (88%).

8-[(8-Meeeeeeeeeeee)eeeeeee]-8,8-eeeeeeee-8-(8-eeeeeeeee-8-eeee)-8M-8-eeeeeeeeee-8,8-eeeee (‌8‌); Meeeeee Meeeeeeee:[‌88‌]

Me e eeeee eeee ee (MMM8)8MM (88 ee, 8.888 eeee) eee MM8MM8 (88 ee, 8.888 eeee) ee M8M (88 eM) eee eeeee e eeee ee eeeeee ‌8‌ (88 ee, 8.888 eeee) ee M8M/eeeeeee (88:8) eeeeeeee ee ee. Meee eeee ee eee eeeeee eeeee eeeeeeeeee, eeee M8M eeeeee ee eeeee. Meeee eeeeeeeeee eeeeeeee eee 8 e, eee eeee eee eeeeeee eeee Me8M (8 × 88 eM), eeeeee eeee eeeee (8 × 88 eM), eeeee (MeMM8), eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Meeeeeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, Me8M/eeeeee 8:88) eeeeeeee eeeeeee ‌8‌ ee e eee eeeee eeeeeeee eeee eeeeeeeee eeeeeeee eeeeeeee ‌8‌ (8.8 ee); eeeee: 88.8 ee (88%).

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) M 88-8, 8888.