Science of Synthesis

Adolfsson, H., Science of Synthesis, (2008) 37, 244.

Regarding the use of tungsten-based systems, Payne and Williams reported in 1959 on the selective epoxidation of maleic, fumaric, and crotonic acids using a catalytic amount of sodium tungstate (2 mol%) in combination with aqueous hydrogen peroxide as the terminal oxidant.[‌62‌] The key to success is careful control of the pH (4–5.5) in the reaction media. These electron-deficient substrates were notoriously difficult to oxidize selectively using the standard techniques (peroxy acid reagents) available at the time. Previous attempts to use sodium tungstate and hydrogen peroxide led to the isolation of the corresponding diols due to rapid hydrolysis of the intermediate epoxides. Significant improvements to this catalytic system have been introduced by Venturello.[‌63‌,‌64‌] It is found that the addition of phosphoric acid and the introduction of quaternary ammonium salts as phase-transfer catalysis reagents considerably increases the scope of the reaction. The active tungstate catalysts are often generated in situ, although catalytically active peroxo complexes (such as {[Me(CH2)5]4N}3PO4[WO(O2)2]4) have been isolated and characterized (‌Scheme 20‌).[‌65‌]

‌Meeeee 88‌ Mee Meeeeeeeee Meeeeeee[‌88‌]

Meeeee eee eeeeeeeee eeee eeeee eeeeeeeeee eee eee eeeeeeeee eeeeeeeeeee ee eeeeeeeee eee-8-eeee eeeeee ee eeeeeee, ee eeeee e eeeeeeeeee eeeeeee-eeee eeeeeeee eeeee.[‌88‌–‌88‌] Mee ee eee eeeeeeeeeeeee eeee eee eeeeeeee eeeeeee ee eee eee ee eeeeeeeeeee eeeeeeee. Mee eeeeeeeeee eeeeeeeeeee ee Meeeee, eeeeeee, eeeeeee ee eeeeeee “eeeeeee” eeeeeeeeeee eeeeeee eeeeeee eee eeeeeeeee eee eeeeeeeeeee eeeeeeeee ee eeeeeeeeeeeeee eeeeeeee. Me eeee eeeeeeee, eeeeee eeeeeeeee (8 eee%), (eeeeeeeeeee)eeeeeeeeee eeee, eee eeeeeeeeeeeeeeeeeeeeee eeeeeeee eeeeeee (8 eee% ee eeee) eee eeeeeeee ee eeeeeeeee eee eee eeeeeeeeeee eeeee eeeeeee eeeeeeee eeeeeeee (88%) ee eee eeeeeeee eeeeeee. Mee eeeeeeeeeee ee eeeeeee eeeeeeee eeeeeee eeeee eee eeeee-eeeeeeeee eeeeeeeeee (88 °M, ee eeeeeee eeeee) eeeee eeee eeeeee eee e eeeeee ee eeeeeeeeee (‌Meeeee 88‌). Mee eeeeee eeeeeeeee ee eeeeeeeeeeeee eeeeee eeeeeee eee eeeeeee eeeeeeee eee ee eeeeeeeee eeeeeeee eeee eee eeeeeeee eeeeeee. Mee eee ee eeeeee eeeeeeeee eeeee eee ee ee eeeeeee eee e eeeeeeeeee eeeeeee ee eeeee eeeeeee-eeeeeee eeeeeeeee. Meee eee (eeeeeeeeeee)eeeeeeeeee eeee ee eeeeeeee ee eeeee eeeeeeeeee eeeee, ee eeeeee ee eeeeeeeeee eeee, eeeeeeeeeeeee eeeee eeeeeeeeeee eee eeeeeeee. Mee eeeeee ee eee eeeee-eeeeeeee eeeeeee eee eeee eeee eeeeeeeeeee ee ee eeeeeeeee eeeeeeeee. Mee eee ee eeeeeeee eeeeeeee eeeeeee ee eeeeeeee ee eee eeeeeeeeeeeee eeeeeeee ee eeeeeeeee eeeee. Mee eeee eee eeeee eee eeeeeeeeeeeee ee eee eeeeeeee eee ee eeeeeeeee eeeeeee eeeeeeeeee- ee eeeeeeeeeeeeeeeeee eeeeeeee eeeeeee eee eeeeeeee ee eeeee-eeeeeeee eeeeee eeeeeeeeee eeeeee eeeee eeeeee. Mee eeeeeeeeeee eeeeee eee eeee eeeeeeee ee eeeeeeeee eeeee eeeeeeeeee, eeee ee eeeeee eeeeeee eeee eeeeeeeee eeeeeeeeeeee eeeeeeee, eee ee eeeeeee eeeeeeeeee eeeeeee eeeeeeeeeeeeeee (eeeeeeee, eeeeee, eeeeeee, eee eeeeee).

‌Meeeee 88‌ Meeeeeeeeee ee Meeeeeee Meeeeee Meeee eee Meeeee Meeeee[‌88‌,‌88‌]

‌Meeeeeeeeee 88‌

e Meeeee (88 eeee), ee eeeeeee.

e Meeeee (88 eeee) ee eeeeeee (8 eM).

M eeeee eeeeeeeeee ee eeee eeeeee ee eee eee eM eeeee eeeee eee eeeeeeeee eee eeeeeeeee. Meee eeeee ee eeeeeeeeeeeee eeeee eeeeee ee eeeeeeeee eeee eeeeeeeeee eeee eee eeeeeeeeeee ee eeee-eeeeeeeee eeeeeeee, eeeee eeeeeeeee eeee-eeeeeee eeeeeeeee eeeeeeeeeee eeeeee eee eeeeeeeeee ee eee eeeeeeee. Me ee eeeeeee, eee eeeeeeeee ee eeeeeeeeeeee eeeee ee 88% eeeeeeeeee eeeee 8 eeeee ee 88 °M, eeeeeeee eee eeeeeeee eeeee eee 8-eeeeeeeeeeeee ee eeee 8% (‌Meeeee 88‌).

Mee eeeeeeeeeee eeeeee eeeeeeeee ee Meeeee eee eeeeeeeeeeee eeee eeeeeee ee eee eeeeee eeeeeeeee ee eeeeeeeeeeee eeeee eeee eeeeeee.[‌88‌] Meeeeeeeeee ee eeeeeeee ee eeeeee eeee ee 88% eeeee eeeee eee eeeeeeeee–eeeeeeee eeeeeeee eeeeeee eeeeee eee 8 eeeeeeeeeee ee eeeeeeee eeeeeeee. Mee eeeeeeeeeee eeeeeee eeeeeeeeee eeee eee Meeeee eeeeeeee eee, ee e eeeeeee eeeeee, eeee eeeeeeeeeeee ee eee eeeeeeeeeeee eeeeeeeeee ee Meeeee eee eeeeeeeee.[‌88‌] Meeeeeeeee eeeeeee ee (eeeeeeeeeee)eeeeeeeeee eeee eee eeeeee eeeeeeeee eee eeeeeeeeee ee eee eeeeeeee eeeeeeeee eeeeeee, eee eee eM ee eee eeeeeeee eeeeee ee eeeeeeee ee 8.8–8 eeee eeeeeee eeeeee eeeeeeeee. Meeee eeeeeee eeeee eee eee eeeeeeeee ee eeeeeeee eeee 8,8,8-eeeeeeeeeeeeeeee[8.8.8]eeee-8-eee, eeeeeeee-8-eeeeeeeeeee, eee 8M-eeeeee, eeee eeee eeeeee ee eeeeeeeeee eee eeee eeeeeeeeeee (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeeeeee ee Me- eee Meeeeeeeeeeeee Meeeeee[‌88‌]

‌Meeeeeeeeee 88‌

M8	M8	M8	Meeeeeeeee (%)	Meeeeeeeeee (%)	Mee
(MM8)8		Me	88	88	[‌88‌]
		M	88	88	[‌88‌]
		M	88	88	[‌88‌]

Meeeeee eeeeee eeeeeeeee eeeeeeee-eeeee eeeeee eee eee eeeeeeeeeee ee eeeeeee eee eeee eeeeeeeeee ee Meeeee eee eeeeeeeee.[‌88‌–‌88‌] Mee eeeeeeeeeeeeeeeeee eeee ee e Meeeee-eeee eeeeeeeeeeeeeeeeeee {[γ-MeM88M88(M8M)8]8−} (‌Meeeee 88‌) ee eeeee ee eeeeeeee eee eeeeeeeeeee ee eeeeeee eeeeee eeeeeeeeee eeeee eeeeeee eeeeeeee eeeeeeee ee eee eeeeeeee eeeeeee. Mee eeeeeeeeeeeeeee ee eeee eeeeee eee eeee eeee eeeeeee eeeeeeeeeee (88%) eee eeeeeeeee eeeeeeeeee ee eee eee ee eee eeeeeeee eeeeeee (88%). Meeeeeee, ee eeee ee ee- eee eee-eeeeeeeeeee eeeeeee, eee eee eeeeeeeeee ee eeee eeeeee eeeeee eeeeeeeeee eeeee eeeeeeee eeeee eeeee 8.88 eee% eeeeeeee (8.8 eee% ee eeeeeeee, ‌Meeeee 88‌). Mee M-eee eeeeeeeee ee eee eeeeeeee eeeeeeeee eeeeeee 88 eeeeeeee eeeee eeeeeeeee ee e eeeeeee [MeM8] eeee. Me eeee eeeeeeee eeeeeeeeeeee ee eee eeeeeeee eeeeeee eeeeeeeee eeee eeeeeeeeee eeeeeeeee ee eee eeeeeeee. Meeeeeeeeee, eee eeeeeeee eee ee eeeeeeeee eee eeeeeeee ee ee eeee eeeee eeeeeee eeee ee eeeeeeee ee eeeeeeeeeee (eeeeeeeeeee ee eeeeeeeeeee). Meeeeeeeeeeee, eee eeeee-eeeeeeeeeee eeeeeee eeee eeeeeeee eeeeeeee eeeeeeeeeeeee ee eeeeeeeeee eeeee eeee eeeeeeee. Mee eeeeeeeee eee ee eeeeeeee eeeeeeee (88%) eeeeeeee eeee eee eeee eeeeeeeeeee eee eeeeeeeeeeee ee eeeeeeeee eeeeeeeeeee eee eeee ee eeeeeeeeee eeeeeeeeeeee.

‌Meeeee 88‌ Meeeeeeeeee Meeee e Meeeeeeeeeeeeeeeeee Meee Meeeeeee[‌88‌]

‌Meeeeeeeeee 88‌

M8	M8	M8	Meeeeeeeeee (%)	Meeee (%)	Mee
Me	M	M	>88	88	[‌88‌]
(MM8)8Me	M	M	88	88	[‌88‌]
(MM8)8		Me	>88	88	[‌88‌]
		M	88	>88	[‌88‌]

Mee eeeeeee eeeeeeeeee eeee eee eeeee eeeeeeeee eeeeeeeeeeeeeee-eeeeeeeee eeeeeeeeeee eeeeee ee eee eeeeeeeeee ee eee eeeeeeee eeeee eee eeeeeeeee eeeeeeee. Me eeeeeeee eeee eeeeeeee, eeeeeee ee eeeeeee eeeeeeeeeeeee eeeeeeeee eeeeeeeee eeee eeee eeeeeeeee. Me Mee eee eeeeeeee eeeeeeee eeeeeeeee eeeeeee eeee eeeeee eeeeeeeee eee eeeeeee eeeeee eeeeeeeeee (MMM: eeeeeeeeeeeeee MeMe8, MeMe8, eee MeMM) eee eee eeeeeeeeeee ee eeeeee eeeeeee eee eeeee eeeeeeee eeee eeeeeee eeeeeeee eeeeeeee.[‌88‌] Me ee eeeee eeee, eeeeeeeee eeee eee eeeeee ee eee eeeeeeee (eeee eeeeeeeeeee ee eeeeeeeeeee eeeeeeeee eee eeee), eeeeeeeee eeeeeeeeee eee eeeeeeeeeee ee eeeeeeee eee eeeeeeee eee eeeee eeeeeee, eeeeeeeeeeee. Mee eeeeeeeeeee eeeeeee eeeeee eeeeeeeee–eeeeeeeee eeeeeeee ee eeeeeeeeeeee eeeeeeeee eee eee eeeeeeeeeee ee eeeee eee eeeeeeeee eeeeeeee, eeeeeee eee eeeeeeeeeee eeeeeeee (eeeeeeeeee 8-eeeeeeeeeeeeeeee) eeeee eeeeee eeeeeeeeee eeee eeeeeeeeeeeeeeeee eeeeeeeeee.

Meeeeee eee eeeeeeeee eeee eeeeeeee ee eee eeeeeeeeeeeeee ee eeeeeeee eeeeeeeee eeeee eeeeeee-eeeeeeeee eeeeeeeee eeeee, eeeeeeeeeeeee, eeeeeeeeeeeee, eee eeeeeeeeeeeeeee eeeeeee.[‌88‌] Meeeeeeee eeeee eeeeeeeeeeeee eeeeeeeee eeeeeeee eeee eeeeeeee eeeeeeee eee eee eeeeeeeeeee ee eeeeeeeeeee eeeeeee ee eeeeeeee ee eeee eeeeeeeeee ee eee eeeeeeeee, eeeeeeee ee eeee eeeee eee eeeeeee eeeeeeeeeee ee eeeeeeee. M eeeeeeeeeeeee eeee eeeeeeeee eeeeeeeeeeeee eeeeeeee eee eeee eeeeeeee ee Meeeee eeee eeeeeeeee ee eee eeeeeeeeeeeeee eee-eeeeeeee eeeee Meeeeeeee MMM-888 eeee ee eeeeeeee eeee ee eee Meeeeeeeee eeeee.[‌88‌,‌88‌] Mee eeeeee eeeeeeee ee eeee eee eee eeeeeeeeeee ee e eeeeee ee eeeeeeee, eee eeee eeeeee eee eeee eeeeeeeeeee ee eee eeeeeeeeeeeee eeeeeeee eee eeeeeeee.

Me e eeeeeeeee eeeeeeee, eeeeeeeee eeeeeeeeeee MMM-88 eeeee eeeeeeeee eeee eeee eeeeeeee.[‌88‌] Meeeeeeeee eeeeeeee eeeee eee eeeee eeeeeeeeeeeeee, eeeeeeeeeeee, eee eeeeeee eeee MMM-88 eee eee eeeeeeee eeeeeeee ee eeeeeee eeee eeeeeeee eeee eee eee eeeeeeeeeee ee eeeeeeeeeeeee eeeeeeeee eeeeeeeee. Mee eeeeeeeee eee eeeeeeee ee eee eeeeeeeeeee ee eeeeee eeeeee eeeeeee eeee eeeeeee eeeeeeee eeeeeeee (88%) ee eeeeeeee eeeeeee; eeeeeee, eeeeeeeeee eee eeeeeeeeeee eee eee eeeeee eeeeeeee eee eeeeee eee. Me eee eeee ee eeeeeeeeeee, eee eeeeeeeeeee eee ee eeeeeeee ee eee eeeeeeee ee eeeeeeee. Mee eee eeeeeeee eeeeeeee (eeee eeee 8%) ee eeeeeeeee eeeeeeeeeeee eeeee eeeee eeeeeeeee.

M eeeeeeeeeeee eeeeeeeeeee eeeeee eee eee eeeeeeeeeee ee eeeeeee ee eeeeeeeeeeeee, eeeeeee eeeee eeeeee-eeeeeeeeeeeee eeeeeeeeee, eee eeee eeeeeeee ee Meeee.[‌88‌] Mee eeeeeeee, eeeee ee eeeee ee eee Meeeeeeeee eeeee eeeeeeee eeee eeee-eeeee eeeeeeeeeeeeeee eeeeeee, eeeee eeeeee eeeeeeeeee eeeeeeeeee. Me eee eeeeeeee ee eeeeeeee eeeeeeee, eee eeeeeeee ee eeeee eeeeeee ee eee eeeeeee, e 8:8 eeeeeee ee eeeeeee eee eeeeeeeeeeeeeeeee, eee, eeee ee eeee eeeeeee ee eeee, eee eeeeeeee eeeeeeee eeeeeeeeeeee eee eee eeeeee ee eeeeeee eeee eee eeeeeeee eeeeeee (‌Meeeee 88‌). Meeeeeeeeee, eeee eeeeeeeeeee eeeeee eee eeee eeeeeeee eeee eee 8-eeeeeeeeeee-8,88-eeeeeee (MMM)/8-eeeeeeeeeeeeeeeeeeeeeee (MMMM) eeeeeee eee eeeeeeee eeeeeeee eeeeeeeee (‌Meeeee 88‌), eee eeee eeeeeeeeee eee eeeeeeeeeee ee eeeeeeee eee eeeeeeeeeeeee ee eeeee eeeeeeeeeee eeeeee. Mee eeeeeeee ee eeeeeeeee ee eeeeeeeeeeeeee eeeeeee eeeee eeeee eee eeee eeeeeeee ee eee eeee eeeeeeee.

‌Meeeee 88‌ Meeeeeeeeee Meeee Meeeee-Meeeeeeeeeeee Meeeeeeeee[‌88‌]

‌Meeeee 88‌ Meeeeeeeeee Meeee Meeeeeee Meeeeeee Meeeeeeee Me Meee[‌88‌]

References

Meeeeee Meeeeeeeeee

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