• Archives of Pharmacal Research
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• v.5 no.2
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• pp.93-96
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• 1982

By using recemic 3-bromo-5-isobutyl-5-methylhydantoin (3a') in dry N, N-dimethylformamide which is a model reagent for asymmetric bromolactonization, bromolactonization of a series of olefinic acids was carried out to furnish corresponding bromolactones in moderate yields.

• YAKHAK HOEJI
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• v.33 no.3
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• pp.206-210
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• 1989

Bromolactonization of 2-Substituted-1-cyclohexenyl-1-acetic acid (1) with 1,3-dibromo-5,5-dimethylhydantoin (dibromantin) in N,N-dimethylformamide gave the corresponding ${\gamma}-bromo-{\beta}-lactone$ (2) and ${\beta}-bromo-{\gamma}-lactone$ (3). The effect of the substituents, the reaction temperature, and the solvent on the regioselectivity was discussed.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.97-101
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• 1982

Depending upon the results obtained by the bromolactonization of olefinic acids (9-11) by means of N-bromosaccharin (4), the influence of the stabilities of the imidic anions resulted from heterolytic cleavage of N-haloimides, such as N-bromosuccinimide (1), N-bromophthalimde (2), and N-bromosaccharin (3) in dry N, N-dimethylformamide on the reactivity is elucidated.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.137-139
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• 1981

Reaction of olefinic acids with N-bromophthalimide in dry N, N-dimethylf-ormamide at room temperature gives bromolactones in good yields.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.327-330
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• 1994

Bromolactonization of 2-substituted-1-cyclohexenyl-1-acetic acids with 1, 3-dibromo-5, 5-dime-thylhydantoin 9DBH) and potsssium tertiary butoxide (t-BuOK0 in anhydrous DMF was found to proceed in a highly regioselective manner. The reaction predominantly resulted in the formation of ${\betha}-lactones$ (greater than 96%).

• Archives of Pharmacal Research
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• v.8 no.1
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• pp.39-41
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• 1985

Bromocycloetherification of a series of 3-and 4-olefinic alcohols using NBS-acetonitrile gave corresponding bromo-tetrahydrofuran with high regio and steroselectivity.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.133-135
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• 1981

Reaction of unsaturated acids with 3-bromo-5, 5-dimenthylhydantoin in dry DMF at room temperature gives bromolactones in 58-91 % yields.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.235.1-235.1
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• 2001

• Archives of Pharmacal Research
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• v.6 no.1
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• pp.45-53
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• 1983

Novel halactolactonizations using NBS (2), NIS(3), and NSP(4) in dry DMF were found to be the most reasonable and efficient procedures. The participation of X as the cylization initiator could be clarly rationalized by experimental results and the regioselectivities of formed halolactones were reasonably elucidated by weakly bridged carbonium ion intermediate.