Non-biological aspects of phosphorus-31 NMR spectroscopy

About twenty spirophosphoranes bearing a P–H bond have been obtained by the reaction of α-hydroxyacids or alkyl tartrates on tricoordinated phosphorus compounds. The stereochemistry is described. Intra- or extracyclic carbonyl groups, especially in the case of two identical ligands, increase the Lewis acid character of the phosphorus atom. Une vingtaine de spirophosphoranes a liaison P–H ont ete prepares en faisant reagir des α hydroxyacides ou des tartrates d'alcoyle sur des substrats a phosphore tricoordine convenables. L'etude stereochimique systematique de ces composes est decrite. La presence des groupements carbonyle a pour influence de renforcer le caractere d'acide de Lewis de l'atome de phosphore, notamment dans le cas des composes contenant deux ligands identiques, que le carbonyle soit intra ou extracyclique.

SPIROPHOSPHORANES A LIAISON P–H D'α-HYDROXYACIDES ET DE TARTRATES D'ALCOYLE: PREPARATION, PROPRIETES—STEREOCHIMIE

https://www.physics.ncsu.edu/clarke/papers/Polymer%2052,%203183%20(2011).pdf

Morphological, mechanical, and electrical properties as a function of thermal bonding in electrospun nanocomposites

Reaction of commercially available trialkyl phosphites with N-phthalylamino acids gave mixtures of seven products, whereas the same reaction carried out with pure triethyl phosphite yielded only the desired 2-(N-phthalytamino)-1-oxoalkanephosphonates. These compounds underwent rearrangement to the same types of products that were obtained with the commercial phosphites. This latter series of reactions was promoted by the presence of dialkyl phosphites.

Reactions of N‐phthalylamino acid chlorides with trialkyl phosphites

In diesem Aufsatz wird ein neuer Copolymerisationstyp beschrieben, der sich dadurch auszeichnet, das das Kettenwachstum spontan ohne Zusatz eines Katalysators ablauft. Ein nucleophiles (MN) und ein elektrophiles Monomer (ME) reagieren zu einem Zwitterion (+MNM), von dem Start- und Wachstumsreaktionen ausgehen. 23 neuartige Copolymerisationen wurden auf der Basis dieses Konzepts ausgearbeitet. Als MN-Monomere wurden funf- und sechsgliedrige cyclische Iminoether, Dihydro-2(3H)-furanimin, ein Azetidin, ein cyclischer Phosphinsaureester und eine Schiff-Base untersucht, als ME-Monomere β-Propiolacton, ein cyclisches Dicarbonsaureanhydrid, ein Sulton, Acrylsaure, Acrylamid, ein β-Hydroxyalkylarylat und Ethylensulfonamid. Bei den meisten Kombinationen entstehen alternierende 1 : 1-Copolymere. Auserdem wurde die alternierende 1 : 1-Copolymerisation eines cyclischen Phosphits mit α-Ketosauren entdeckt.

Spontan ablaufende alternierende Copolymerisation über Zwitterion‐Zwischenstufen

Polymerization via Zwitterion. 16. Alternating Copolymerization of Cyclic Phosphite with α-Keto Acid

A new route to pentacovalent cyclic acyloxyphosphoranes

Spontaneous alternating copolymerizations of 2-phenyl-1,3,2-dioxaphospholane (MN) with p- and with o-formylbenzoic acids (ME) were examined. The copolymerizations took place without catalysts affording the copolymer 3 via zwitterion 6. The copolymerizations involve the oxidation of the phosphorus monomer and the reduction of formylbenzoic acid. The scheme of the copolymerizations was presented. The yields of copolymers were quite different between these two copolymerizations. With ortho acid, the copolymer yield was low due to producing phthalide 4.

Polymerization via zwitterion. 20. Alternating copolymerizations of 2-phenyl-1,3,2-dioxaphospholane with p-and o-formylbenzoic acids

We have d e v e l o p e d a s e r i e s o f new c o p o l y m e r i z a t i o n s which occur without added catalyst and proceed through zwitterion intermediates (SAEGUSA et al, 1975a, b; 1976a; 1977a). In these copolymerization, a monomer of nucleophilic reactivity (M N) reacts with another monomer having electrophilic reactivity (M E ) to _ generate a key + intermediate of zwitterion MN-M E . On the basis of this concept we found new polymer synthesis reactions to form polyphosphinate 7 from 4 and 2a (SAEGUSA et al, 1976b) and polyphosphate 8 from 1 and 5 ~SAEGUSA et al, 1977b). In both cases, 1 and 4 acted as nucleophilic monomer (M N) and 2 and 5

Alternating copolymerizations of dioxaphospholanes with acrylic acid derivatives and with α-keto acids. New synthesis of polyphosphonates

The reaction of phenylglyoxylic acid (6), an α-keto acid, with 2-phenoxy-4, 4,5,5-tetramethyl-1,3,2-dioxaphospholane (7) produced poly (benzylidene carboxylate) (8), a poly (α -ester), and a cyclic phosphate (9). This reaction (2) provides a new. method of preparation of poly (α -ester) s. In the reaction, the keto oxygen atom of6 was deoxygenated by7 to give polymer8 (Deoxy-Polymerization). The structure of the polymer end group was elucidated, and the reaction mechanism has been presented.

Tsunenori Yokoyama

Papers

Polymerization via Zwitterion. 16. Alternating Copolymerization of Cyclic Phosphite with α-Keto Acid

A new route to pentacovalent cyclic acyloxyphosphoranes

Polymerization via zwitterion. 20. Alternating copolymerizations of 2-phenyl-1,3,2-dioxaphospholane with p-and o-formylbenzoic acids

Alternating copolymerizations of dioxaphospholanes with acrylic acid derivatives and with α-keto acids. New synthesis of polyphosphonates

Deoxy-polymerization of phenylglyoxylic acid using a cyclic phosphite as deoxygenating agent a new synthesis of poly(α-ester)