1217-12-5Relevant articles and documents
McAlister et al.
, p. 1666 (1977)
Dimethyl octamethyltricyclo[4.2.2.02,5] deca-3,759-triene-7,8-dicarboxylate (Cookson's diester) revisited: Cope rearrangement and epoxidation site selectivity
Warrener, Ronald N.,Elsey, Gordon M.,Pitt, Ian G.,Tiekink, Edward R.T.,Russell, Richard A.
, p. 1075 - 1078 (1994)
Dimethyl octamethyltricyclo[4.2.2.02,5]deca-3,7,9-triene-7,8-dicarboxylate (Cookson's diester) (8) is rearranged thermally via a double Cope reaction to its ring-degenerate isomer (14). The structure of diester (8) (indirectly) and the rearrangement product (14) (directly) are placed on an unequivocal base by X-Ray structure analysis. AMI semi-empirical calculations support the preferential formation of (8) from the reaction of DMAD with transient intermediate diene (7). Epoxidation studies (mCPBA) have been conducted and firm site selectivities determined. A correction is made to an earlier report on the epoxidation selectivity of (18).
Quantum amplified isomerization in polymers based on triplet chain reactions
Ferrar, Lorraine,Mis, Mark,Dinnocenzo, Joseph P.,Farid, Samir,Merkel, Paul B.,Robello, Douglas R.
, p. 5683 - 5692 (2008/12/22)
(Graph Presented) Photoinitiated triplet quantum amplified isomerizations (QAI) of substituted Dewar benzene derivatives in polymeric media are reported. The quantum efficiencies and the ultimate extents of reactant-to-product conversions increase significantly with the incorporation of appropriate co-sensitizers; compounds whose triplet energies are similar to or lower than that of the sensitizer and close to that of the reactant. These co-sensitizers serve to promote chain-propagating energy transfer processes and thereby increase the action sphere of photosensitization. Isomerization quantum yields increase, as predicted, with increasing concentrations of the reactants and the co-sensitizers. Chain amplifications as large as ～16 and extents of conversion that approach 100% have been achieved. Mechanistic schemes are proposed to account for the dynamics of the inherent energy transfer processes and provide a predictively useful model for the design of a new class of photoresponsive polymers based on changes in the refractive index of the materials.
Cycloaddition of thiophene S-oxides to allenes, alkynes and to benzyne
Thiemann, Thies,Fujii, Hideki,Ohira, Daisuke,Arima, Kazuya,Li, Yuanqiang,Mataka, Shuntaro
, p. 1377 - 1384 (2007/10/03)
Thiophenes have been treated with alkynes in the presence of m-chloroperoxybenzoic acid to give substituted arenes as cycloadducts. Alternatively, thiophene S-oxides have been prepared by oxidation from thiophenes and have been subjected to cycloaddition with alkynes in a subsequent step. The outcome of the reaction is dependent on the steric demand of the thiophene S-oxide. Some thiophene S-oxides can be reacted at temperatures as high as 140°C without decomposition. Thiophenes as deoxygenated products are the main by-products. Reactions of thiophene S-oxides with allenes give in part thiabicyclo[2.2.1]heptene S-oxides of type 12a and 13 along with aromatized products. Thiophene S-oxides also cycloadd to benzyne.
