Molybdenyl acetylacetonate

Molybdenum(VI) dioxyacetylacetonate (molybdenyl acetylacetonate) was first prepared by Gach1 by the action of acetylacetone upon molybdenum(VI) oxide at room temperature. Since he also isolated a small quantity of the same compound by the reaction between molybdenum (II) hydroxide and acetylacetone, he believed the compound to be Mo(C5H702)2. Rosenheim and Bertheim2 later prepared the compound by refluxing an ethanolic solution of acetylacetone with molybdic acid. They correctly identified the product as molybdenyl acetylacetonate. Morgan and Castell3 later duplicated the preparation of Rosenheim and Bertheim and verified their formula. 

Molybdenyl acetylacetonate, 6 147 12-Molybdosilicic acid, 1 127 analysis of, 1 128 Monazite, extraction of, 2 38 separation of rare earths from, 2 56... 

The polyitnide bead bearing a triazole residue was used to immobilize a stable and active Mo(VI) epoxidation catalyst. The polyimide was refluxed with molybdenyl acetylacetonate in ethanol for 3days. Upon completion, a polyimide-Mo complex catalyst was filtered and extracted with ethanol in a Soxhiet apparatus for 3 days. The supported complex was dried thoroughly under vacuum. The molybdenum content was measured by inductively coupled plasma (ICP) to be l.OSmmolg for PI-DAT.Mo and l. lOmmolg for CPI-DAT.Mo. 

Remarkably, in contrast to the parent 1,3-oxathiane and the corresponding dithiane systems, the sulfones 1,3-oxathiane 3,3-dioxide and its 6-methyl derivative (59 R = H, Me), obtained by reaction of the 1,3-oxathianes with /-butyl hydroperoxide and molybdenyl acetylacetonate, are deprotonated, and subsequently react with a variety of electrophiles, at the 4-position (Scheme 21) <86CL1655>. 

Complex molybdenyl acetylacetones also act as catalysts for trioxane polymerization. The mechanism that is visualized involves formation of a coordinated intermediate [75] ... 

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