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Lead(IV) acetate or lead tetraacetate is an metalorganic compound with chemical formula Pb(C 2 H 3 O 2) 4. It is a colorless solid that is soluble in nonpolar, organic solvents, indicating that it is not a salt. It is degraded by moisture and is typically stored with additional acetic acid. The compound is used in organic synthesis. [2]
The Criegee oxidation is a glycol cleavage reaction in which vicinal diols are oxidized to form ketones and aldehydes using lead tetraacetate. It is analogous to the use of periodate (Malaprade reaction) but uses a milder oxidant. This oxidation was discovered by Rudolf Criegee and coworkers and first reported in 1931 using ethylene glycol as ...
It was also observed, that the addition of lead tetraacetate can facilitate the Stieglitz rearrangement of amine derivatives. [32] After the formation of the activated amine derivative intermediate by coordination to the lead center, the following rearrangement again proceeds via migration of the aromatic group under formation of a C–N bond ...
Tarnished lead (left) and shiny lead (right) Compounds of lead exist with lead in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) compounds are typically strong oxidants or exist only in highly acidic solutions. [1] Red α-PbO and yellow β-PbO The mixed valence oxide Pb 3 O 4 Black PbO 2 which is a strong ...
This lack of tight radical pairing is also supported by the observation that alkyl radicals generated by Barton conditions can undergo radical cyclization while analogous intermediates generated by lead tetraacetate oxidation do not. [13] In rare cases, it appears that the alkoxyl radical may epimerize before hydrogen atom abstraction. [14]
The addition of the two molecules typically proceeds in a step-wise fashion to the addition product, usually in equilibrium, and with loss of a water molecule (hence the name condensation). [3] The reaction may otherwise involve the functional groups of the molecule, and is a versatile class of reactions that can occur in acidic or basic ...
Lead oxides are a group of inorganic compounds with formulas including lead (Pb) and oxygen (O). Common lead oxides include: Lead(II) oxide, PbO, litharge (red), massicot (yellow) Lead tetroxide or red lead, Pb 3 O 4, minium, which is a lead (II,IV) oxide and may be thought of as lead(II) orthoplumbate(IV) [Pb 2+] 2 [PbO 4− 4], vivid orange ...
3-Hydroxylcarbonyls, called aldols, release water upon standing at room temperature: RC(O)CH 2 CH(OH)R' → RC(O)CH=CHR' + H 2 O. The reaction is induced by dehydrating reagents. For example, 2-methyl-cyclohexan-1-ol dehydrates to 1-methylcyclohexene in the presence of Martin's sulfurane, which reacts irreversibly with water. [6] [7]