Rearrangement In based

The 2-aminophenoxy triazine (50) readily undergoes the Smiles rearrangement in base (equation 23) (70JHC981), or photochemically (70TL1467). Budziarek reported a similar reaction with the naphthyl derivative (51 Scheme 37) (7lJCS(C)74>. 

Another 4,5-epoxymorphinan with a rigid C-ring has been prepared(22t>) and described as 7,14-cyclodihydrocodeinone (137), where the cyclopropane ring is within the C-ring. The hasubanan-6-one hydrochloride (135) was reacted with dimethyl sulfate to give 136, which rearranged in base to 7,14-cyclodihydrocodeinone (137). The photolysis of these compounds has been described/221 No biological data were reported. 

Diethyl trichloromethylphosphonate (16) reacts with ribonucleotides, and presumably with other vicinal 1,2-diols, in the presence of triethyl-amine to give a mixture of the 2 - and 3 -phosphates. The readily available ct-hydroxyphosphonate esters (17) rearrange in base to the phosphate... 

The rearrangement of adducts of enol acetates derived from a-diketones has been reported. An interesting application of this principle was in a model study for the synthesis of acorenones (Scheme 14) in which the adduct (49) underwent rearrangement in base to (50) which was cleaved with lead tetra-acetate to generate the spirocyclic product (51). ... 

Diketones rearrange in base to 2-hydroxycarboxylic acids (benzylic acid rearrangement). Although possible in principle for all 1,2-diketones, this reaction is only common for nonenolizable species. 

Henkel Rearrangement of Benzoic Acid and Phthalic Anhydride. Henkel technology is based on the conversion of benzenecarboxyhc acids to their potassium salts. The salts are rearranged in the presence of carbon dioxide and a catalyst such as cadmium or zinc oxide to form dipotassium terephthalate, which is converted to terephthahc acid (59—61). Henkel technology is obsolete and is no longer practiced, but it was once commercialized by Teijin Hercules Chemical Co. and Kawasaki Kasei Chemicals Ltd. Both processes foUowed a route starting with oxidation of napthalene to phthahc anhydride. In the Teijin process, the phthaHc anhydride was converted sequentially to monopotassium and then dipotassium o-phthalate by aqueous recycle of monopotassium and dipotassium terephthalate (62). The dipotassium o-phthalate was recovered and isomerized in carbon dioxide at a pressure of 1000—5000 kPa ( 10 50 atm) and at 350—450°C. The product dipotassium terephthalate was dissolved in water and recycled as noted above. Production of monopotassium o-phthalate released terephthahc acid, which was filtered, dried, and stored (63,64). 

Phthalic anhydride and diethyl phthalate are easily converted with hydrazine into 4-hydroxyphthalazin-l(2/f)-one. Its substituted derivatives have been prepared using substituted hydrazines, substituted phthalic anhydrides, or diesters or disodium salts of substituted phthalic acids (Scheme 81). However, condensation of phenylhydrazine with phthalic anhydride gives only a small amount of the corresponding phthalazine, the main product being 2-anilinophthalimide. This can be rearranged in the presence of base into the phthalazine derivative. For the preparation of 2,3-disubstituted derivatives, 1,2-disub-stituted hydrazines are reacted with the appropriate phthalic anhydrides or phthaloyl chlorides. Derivatives of 4-amino- or 4-hydrazino-phthalazin-l(2iT)-one have been prepared either from the corresponding monothiophthalimide and 3-aminoisoindolin-3-one (1S4) or from ethyl 2-cyanobenzoate (155) and hydrazine hydrate (Scheme 82). Similarly,... 

The Bamford-Stevens decomposition of tosylhydrazones by base has been applied to steroids, although not extensively. It has been demonstrated that the reaction proceeds via a diazo compound which undergoes rapid decomposition. The course of this decomposition depends upon the conditions in proton-donating solvents the reaction has the characteristics of a process involving carbonium ions, and olefins are formed, often accompanied by Wagner-Meerwein-type rearrangement. In aprotic solvents the diazo compound appears to give carbene intermediates which form olefins and insertion products ... 

Smiles rearrangement was observed also in base-catalyzed cyclization of 2-hydroxy-2 -nitrodiphenylsulfones leading to low yields (about 5%) of phenoxathiine 10,10-dioxides (34JCS422, 56JA5357). However, this type of compounds can be easily prepared by other methods (05CB1411, 06CB1340). 

Positive photoresists, by contrast, are based on water-soluble novolak resins with naphthalene diazoquinone sulfonate (NDS) as the photosensi-tiser. On photolysis the NDS causes a rearrangement in the polymer to yield nitrogen gas plus an indene carboxylic acid. This latter functional group considerably increases the solubility of the polymer, hence solubilising those areas of the polymer that had been exposed to light. 

A formulation of electronic rearrangement in quantum molecular dynamics has been based on the Liouville-von Neumann equation for the density matrix. Introducing an eikonal representation, it naturally leads to a general treatment where Hamiltonian equations for nuclear motions are coupled to the electronic density matrix equations, in a formally exact theory. Expectation values of molecular operators can be obtained from integrations over initial conditions. 

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