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Tetrahedron | 1968

Triaminooxyphosphonium dipolar ions and triaminodioxy phosphoranes from the reaction of triaminophosphines with α-diketones: Demonstration of the co-existence of 4-coordinated and 5-coordinated phosphorus in solution. P31 NMR spectra☆

Fausto Ramirez; A. V. Patwardhan; H.J. Kugler; C.P. Smith

Abstract The phosphorus of trisdimethylaminophosphine added to the oxygen of the α-diketone, benzil, and gave a 1:1 adduct. This adduct could be isolated in two crystalline forms: one of them was a triaminooxyphosphonium dipolar ion, and the other was a cyclic triaminodioxyphosphorane. Solutions of these crystalline adducts contained the same molecular species in equilibrium with each other. Certain solvents favoured the cyclic form with 5-coordinated phosphorus, while others favoured the dipolar ion with 4-coordinated phosphorus. The value of the P31 NMR shifts varied from +30·2 ppm vs H3PO4 in 0·8M hexane to +13·1 ppm in 1·2M methylene chloride solutions. In methylene chloride solutions, the value of the shift varied significantly with concentration. The 1:1 adducts made from the reactions of the 5-membered cyclic triaminophosphines 2-N-pyrrolidino-, 2-dimethylamino-, and 2-methoxy-1,3,2-diazaphospholanes with benzil existed exclusively as cyclic triaminodioxyphosphoranes in the crystalline state and in solutions. The reaction of acenaphthenequinone with the cyclic aminophosphines produced the corresponding aminophosphine oxides via unstable adducts with POC bonds, which were formed at −70°.


Journal of the American Chemical Society | 1967

Formation of phosphorus-oxygen bonds in the reactions of triaminophosphines with o-quinones, vicinal triketones, and xoxmalonic esters. Triaminooxyphosphonium dipolar ions and triaminodioxaphosphoranes. Phosphorus-31 nuclear magnetic resonance spectra

Fausto Ramirez; A. V. Patwardhan; H.J. Kugler; C. P. Smith


Journal of Organic Chemistry | 1967

Molecular rearrangements during solvolyses of pentaoxyphosphoranes. Polyketones derived from phthalaldehyde and terephthalaldehyde

Fausto Ramirez; S. B. Bhatia; A. V. Patwardhan; C. P. Smith


Journal of the American Chemical Society | 1965

A New Synthesis of α,β-Dihydroxy Ketones via Oxyphosphoranes. Condensation of Aliphatic α-Diketones with Aldehydes by means of Trialkyl Phosphites. P31 and H1 Nuclear Magnetic Resonance Spectra1,2

Fausto Ramirez; A. V. Patwardhan; N. Ramanathan; N. B. Desai; C. V. Greco; S. R. Heller


Journal of the American Chemical Society | 1964

The Reaction of Trialkyl Phosphites with Aliphatic Aldehydes. P31and H1Nuclear Magnetic Resonance Spectra of Tetraoxyalkyl Phosphoranes

Fausto Ramirez; A. V. Patwardhan; Stephen R. Heller


Journal of the American Chemical Society | 1965

Reaction of Triaminophosphines with Oxomalonic Esters, Vicinal Triketones, and o-Quinones. Triaminooxyphosphonium Dipolar Ions1

Fausto Ramirez; A. V. Patwardhan; C. P. Smith


Journal of the American Chemical Society | 1965

The Hydrolysis of Five-Membered Cyclic Oxyphosphoranes to Cyclic Phosphate Esters. P31Nuclear Magnetic Resonance and Stereoisomerism at Phosphorus in Cyclic Phosphates1,2

Fausto Ramirez; A. V. Patwardhan; N. B. Desai; S. R. Heller


Journal of Organic Chemistry | 1968

Reactions of trialkyl phosphites with polycyclic p- and o-quinones. Anthraquinone, the pyrenequinones, and the naphthoquinones

Fausto Ramirez; S. B. Bhatia; A. V. Patwardhan; Eugene H. Chen; C. P. Smith


Journal of Organic Chemistry | 1965

Pentaoxyphosphoranes from the Reaction of Trialkyl Phosphites with α-Ketoaldehydes and with Vicinal Triketones. Condensations of α-Ketoaldehydes with α-Diketones. P31 and H1 Nuclear Magnetic Resonance Spectra1

Fausto Ramirez; A. V. Patwardhan; C. P. Smith


Journal of the American Chemical Society | 1963

A New Synthesis of α,β-Dihydroxy-γ-ketoesters and of α,β-DihydroxyketonesviaCyclic Oxyphosphoranes

Fausto Ramirez; A. V. Patwardhan; N. B. Desai; N. Ramanathan; C. V. Greco

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Fausto Ramirez

State University of New York System

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C. P. Smith

State University of New York System

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H.J. Kugler

State University of New York System

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N. B. Desai

State University of New York System

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C.P. Smith

Stony Brook University

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N. Ramanathan

State University of New York System

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