Novel Method for the Preparation of Acid Anhydrides by Means of Diphenylmercury and Tertiary Phosphine

Abstract

heptafluorobutyranilide was obtained in 21% yield as colorless needles, m.p. 97°. The product was identical with the amide prepared directly from p-anisidine.Products from N-Phenylmalonamic Acid.-Treatment of this amic acid with trifluoroacetic or heptafluorobutyric anhydrides gave a colorless powder in yields of 60-80% (calculated as dehydration product). The melting point varied with different preparations (210°, 186-190°dec.) and appeared to depend on the rate of heating. The infrared spectrum contained bands at 3.08 and 5.95 µ.

Explorations into New Reaction Chemistry

“…The characteristic feature of these reactions is that they proceed under “mild and neutral” conditions without any assistance from added acids or bases. The first example of this type of condensation in regard to acylation reactions was reported from our laboratory in 1963 1. Treatment of diphenyl‐ or bis( p ‐methoxyphenyl)mercury with tri‐ n ‐butylphosphane in the presence of two equivalents of carboxylic acid leads to formation of the corresponding acid anhydride in high yield together with mercury and tri‐ n ‐butylphosphine oxide (Scheme ) 1.…”

“…The first example of this type of condensation in regard to acylation reactions was reported from our laboratory in 1963 1. Treatment of diphenyl‐ or bis( p ‐methoxyphenyl)mercury with tri‐ n ‐butylphosphane in the presence of two equivalents of carboxylic acid leads to formation of the corresponding acid anhydride in high yield together with mercury and tri‐ n ‐butylphosphine oxide (Scheme ) 1. In this reaction two molecules of carboxylic acid undergo condensation with the help of a hydrogen acceptor (diaryl mercury) and an oxygen acceptor (tri‐ n ‐butylphosphane) to give the anhydride.…”

Synthesis of Acid Halides, Anhydrides and Related Compounds

“…80% (equation 28). 98 The reaction is regarded as proceeding through initial formation of phenylmercury(II) carboxylates. Oxidation-reduction reactions with tri-n-butylphosphine as reducing agent and electron deficient alkenes as oxidizing agents were also proposed as a means of obtaining acid anhydrides from carboxylic acids (equation 29).99 trans-Dibenzoylethylene as electron acceptor in this reaction allows the preparation of aliphatic acid anhydrides in good yield.…”

Oxidation–Reduction Condensation of Diazaphosphites for Carbon–Heteroatom Bond Formation Based on Mitsunobu Mechanism

“…Alternatively, the oxidation–reduction condensation reaction of alkoxydiphenylphosphines with acidic nucleophiles using quinones has emerged one of the most powerful synthetic tools for carbon–heteroatom bond formation in organic synthesis due to the mild and neutral reaction conditions since its first report in 1963 by Mukaiyama . This condensation reaction employs weak reductants and oxidants without the addition of acids or bases.…”