• Journal of the Korean Society of Industry Convergence
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• v.6 no.2
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• pp.123-129
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• 2003

Oxindoles(6a-g) are obtained by rhodium(II)-catalyzed Wolff rearrangement of diazoquinolinediones in moderate yields. Treatment of 6a-g oxindole derivatives reacted with CAN in acetonitrile at room temperature to gave 7a-g isatins in good yields. The structures of these compound were identified by MP, IR and NMR-spectra.

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.395-401
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• 1997

The substituent effects in the gas-phase rearrangement of carbenes to ketenes involved in the Wolff reaction have been investigated theoretically using the AM1 method. In the initial state, carbene, there is a relatively strong vicinal n-σ* interaction between the lone pair (n) and carbonyl group (σ*). In the bridged transition state (TS), electronic charge is transferred from the migrating ring (Z-ring) toward the nonmigrating ring (Y-ring). The carbenes are stabilized by an electron donor Y (δσY < 0) whereas the TS is stabilized by an electron acceptor Y (δσY > 0). Multiple regression analysis of log (kYZ/kHH)(=-δΔG≠/2.3RT) leads to a relatively large negative cross-interaction constant, ρYZ=-0.53, log (kYZ/kHH)=2.96 σY--1.40 σZ-0.53 σY-σZ reflecting an extensive structural change in the transition state due to the stabilization of the initial state by the vicinal n-σ* overlap. When the solvent (water) effects are accounted for by the SM2.1 model of the Cramer and Truhlar method, the magnitude of all the selectivity parameters, ρY-, ρZ and ρYZ (=-0.66) are increased.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.644-650
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• 1989

Syntheses of phthalide sulfone 2 and naphthalenone 6 followed by new ring annelation methodology of Michael addition using the sulfone anion developed by Hauser-Rhee, furnished linear tetracyclic ring system compound 11. The double bond existing in A-ring of 11 was used to convert to carbomethoxy compound 16, possessing one carbon atom more via Arndt-Eistert synthesis and Wolff rearrangement. Cyclization and hydroxylation of 16 completed the construction of (${\pm}$)-7-Deoxyaklavinone (18).

• Journal of the Korean Graphic Arts Communication Society
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• v.12 no.1
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• pp.17-34
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• 1994

Recently, the photopolymer made of novolak resin as the base and the naphthoquinonediazide(NQD) as the photoreactive compound is used for the presensitized plate(PS plate). The reaction mechanism of the NQD-novolak resin on light exposure is considered. Upon exposure it undergoes a Wolff rearrangement, via ketene intermediate which react with water ti form an 3-indene carboxylic acid. It was also found that NQD type resin in this experiment shows a high relative sensitivity compared with imported sample from Japan.