Hydrolysis of electrophilic olefins. I. Kinetic studies on the hydrolysis of p-dimethylaminobenzylidene derivatives of active methylene compounds.
抄録
The dissociation constants (Ka) of the conjugate acids of the p-dimethylaminobenzylidene derivatives (I) of various active methylene compounds (XYCH2) were determined. Alkaline hydrolysis of I was studied kinetically in 30% (v/v) ethanol at 25°C. The rates of nucleophilic attack of a hydroxide ion on the carbon-carbon double bonds of I were linearly correlated with the corresponding pKa values. Thus the pKa values are suggested to be useful parameters to evaluate the relative activating ability of the X and Y groups to support the attack of nucleophiles on compounds of the type XYC=CHAr. In the hydrolysis of structurally similar compounds α-(substituted benzoyl)-p-dimethyl-aminocinnamonitriles, the rates of carbon-carbon bond fission of an uncharged addition intermediate and those of carbon-carbon double bond formation from a carbanion intermediate were also correlated with the dissociation constants (KAMa) of the corresponding substituted benzoylacetonitriles. The pH-rate profile and the relationship between rates and Ka (or KAMa) suggested that the carbon-carbon bond fission of the uncharged intermediate is the rate-determining step in the alkaline hydrolysis of I.
収録刊行物
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- CHEMICAL & PHARMACEUTICAL BULLETIN
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CHEMICAL & PHARMACEUTICAL BULLETIN 29 (10), 2743-2752, 1981
公益社団法人 日本薬学会
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詳細情報 詳細情報について
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- CRID
- 1390282679142835584
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- NII論文ID
- 130003768862
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- ISSN
- 13475223
- 00092363
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- 本文言語コード
- en
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- データソース種別
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- JaLC
- Crossref
- CiNii Articles
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- 抄録ライセンスフラグ
- 使用不可