Phosphororganische Verbindungen, 64: Allyl‐Propenyl‐Umlagerungen Das elektrochemische Verhalten einiger Propenylverbindungen

Abstract

Allyl-aryl-sulfone, Allyl-diphenyl-phosphinoxid, Allylphosphonsiiure-diathylester, Allyltriphenyl-phosphoniumbromid und Allyl-triphenyl-arsoniumbromid lagern sich an basischem A1203 in die entsprechenden I-Propenyl-Verbindungen um. Allyl-diphenyl-phosphin und Diallyl-phenyl-phosphin isomerisieren sich unter Mitwirkung von Natriumathylat zu den cntsprechenden 1 -Propenyl-Verbindungen. Die Allyl-und 1 -Propenyl-Verbindungen werden IR-und NMR-spektroskopisch sowie polarographisch charakterisiert. -Bei der kathodischen Spaltung von 1-Propenyl-triphenyl-phosphoniumbromid entstehen 92% Triphenylphosphin und Propen. 1 -Propenyl-phenyl-sulfon wird elektrochemisch in Propen und Benzolsulfinsliure aufgespalten.Organic Phosphorus Compounds, 643) Allyl-Propenyl RearrangementsThe Electrochemical Behaviour of some Propenyl Compounds4) Allyl aryl suffones, allyldiphenylphosphine oxide, diethyl allylphosphonate, allyltriphenylphosphonium bromide and allyltriphenylarsonium bromide undergo rearrangement on basic A1203 (the last-named allyl compound only to a limited extent) to give the corresponding 1 -propenyl compounds. Allyldiphenylphosphine and diallylphenylphosphine also rearrange on treatment with sodium ethoxide to give the corresponding I-propenyl compounds. The allyl and I-propenyl compounds are characterised by i.r. and n.m.r. spectroscopy as well as polarographically.Cathodic cleavage of (1-propcny1)triphenylphosphonium bromide, affords triphenylphosphine and propene in 92% yield. 1-Propenyl phenyl sulfone is cleaved electrochemically to propene and benzenesulfinic acid.Es ist lange bekannt, daR sich Allyl-aryl-Verbindungen unter dem EinfluR von Basen in 1-Propenyl-aryl-Verbindungen urnlagern. Diese Isomerisierung verlauft besonders leicht, wenn das nach Deprotonierung entstehende Allyl-Anion durch elektrophile Gruppen stabili-1 ) Auszug aus der Diplomarbeit I. Ertel, Univ. Mainz 1968.

Crown Ether Base: Highly Active, Regioselective and Reusable Catalytic Systems for Double Bond Migration in Allylic Compounds

“…As far as the literature data is concerned, basic catalysts have been used for the isomerization of O ‐allyl ethers, but not for the isomerization of O ‐allyl acetals and O ‐allyl esters. The following allyl ethers, among the examined in this work, were isomerized in the presence of basis catalytic systems: 2 ( Q = t ‐BuO, t ‐BuOK), 3 (PhCH 2 , t ‐BuOK), 4 ( neo ‐menthyl O , LDA or t ‐BuOK), 6 (PhO, t ‐BuOK or LDA, or Vercade's super‐base,), 7 ( t ‐BuOK), 8 ( t ‐BuOK), and 9 ( t ‐BuOK). As mentioned above, the catalytic systems crown ether‐base type have not been applied to the O ‐allyl compounds isomerization so far.…”

“…As far as P ‐allyl systems are concerned, the isomerization of allyl diphenyl phosphine 27 is known from the literature, whereas the isomerization of diallyl phosphine 28 has not been described so far. Compound 27 was isomerized in the presence of 18‐Crown‐6/KOH in benzene, and NaOEt in EtOH . It was shown that the isomerization of various N ‐ and P ‐allyl and diallyl compounds could be effectively realized in mild conditions, using safe and easy to evaporate solvents and in short reaction time with the aid of the various type of base/crown ether systems selected appropriately to the N ‐ and P ‐allyl substrate reactivity.…”

Sharpless Asymmetric Dihydroxylation of trans-Propenylphosphonate by Using a Modified AD-mix-α and the Synthesis of Fosfomycin

“…Phosphonate 3b was once synthesized by a rather tedious method because a simpler method through a base-catalyzed isomerization of dibenzyl 2-propenylphosphonate, the reaction originally reported for diethyl phosphonate, was unsuccessful . Among the other methods published, , the palladium-catalyzed reaction 16a of alkenyl halides and dialkyl phosphite (HP(O)(OR) 2 ) was investigated.…”