G. A. Ivkova

Caged phosphorane with P-C bond based on chloral and 4,5-dimethyl-2-(2-oxo-1,2-diphenylethoxy)-1,3,2-dioxaphospholane

The key methods of caged phosphoranes synthesis are analyzed. Reaction of 4,5-dimethyl-2-(2-oxo-1,2-diphenylethoxy)-1,3,2-dioxaphospholane (prepared from the meso-form of 2,3-butanediol) with chloral has yielded the caged phosphorane containing a phosphorus-carbon bond: 1,1-(1,2-dimethylethylenedioxy)-3,4-diphenyl-6-trichloromethyl-2,5,7,1-trioxaphosphabicyclo[2.2.11,4]heptane; spatial structure of the product has been elucidated with X-ray diffraction analysis.

Reaction of ethyl trifluoropyruvate with 2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[d]-1,3,2-dioxaphosphorin-4-one. Effect of exocyclic substituent on chemoselectivity

Benzo[d]-1,3,2-dioxaphosphorin-4-ones (P-phosphorrylated cyclic derivatives of salicylic acid), containing a nucleophilic phosphorus atom and electrophilic endocyclic carbonyl group, exhibit a specific reactivity. They react readily to increase the ring to sevenmembered one by the action of activated systems with multiple bonds [1–6]. Introduction to the phosphorus atom of the benzo[d]-1,3,2-dioxaphosphorin-4-one an exocyclic substituent, the λσ-diazaphosphol fragment containing the P atom, could change the direction of the interaction with such activated unsaturated systems as carbonyl compounds. Indeed, it appears that the weak-acceptor and bulky diazaphosphol moiety in the compound I leads to a change of the reaction direction with ethyl trifluoropyruvate. In contrast to the ordinary derivatives of benzo[d]1,3,2-dioxaphosphorin-4-one [7], here predominates (>90%) the formation of a (Р–С → Р–ОС)-regrouping product, the 1,3,2-dioxaphosphepin derivative II involving a dioxaphosphorine fragment only. The trifluoropyruvate ester contains a prochiral carbonyl group, which is the source of the second chiral center (C), causing the formation of two diastereomers (55:45) of the reaction product II, whose structure was established by the NMR and mass spectrometry. The H, С–{H}, Р–{H} NMR spectra of the compound II purified from the volatile impurities contain a double set of signals that can not be attributed to one or other diastereomers due to their close arrangement. The minor reaction direction (<8%) is the formation of a pentacoordinated phosphorus atom derivative III, whose signals in the Р–{H} NMR spectrum are: –32.3 d, –34.1 d (5:1) (P), 254.0 br.d (P) (JРСР 87.2–87.3 Hz).

Synthesis and Some Properties of 2-(5-Methyl-2-Phenyl-2H-1,2,3-Diazaphosphol-4-yl)-4H-Benzo[d]-1,3,2-Dioxaphosphorin-4-One

Abstract 2-(5-Methyl-2-phenyl-2Н-1,2,3-diazaphosphol-4-yl)-4H-benzo[d]-1,3,2-dioxaphosphorin-4-one 1 readily reacts with hexafluoroacetone, mesoxalic acid diethyl ester, trifluoropyruvic acid ethyl ester and chloral to give 2-(5-methyl-2-phenyl-2H-1,2,3-dizaphosphole-4-yl)-derivatives of 1,3,2- and 1,4,2-dioxaphosphepines. GRAPHICAL ABSTRACT

Cycloexpansion Reactions in Benzo[e]-1,3,2-diheterophosphorin-4-ones and 4-Oxo-1,3,2-dioxaphospholanes

Abstract The peculiarities of the reactions of 2-R-benzo[d]-1,3,2-dioxaphosphorin-4-ones, 2-R-naphtho[d]-1,3,2-dioxaphosphorin-4-ones, 2-R-8-azabenzo[e]-1,3,2-dioxaphosphorin-4-ones, and 2-R-1,3,2-dioxaphospholan-4-ones with unsaturated compounds are summarized in the review. The reactions proceed in the mild conditions and lead to the formation of the seven- and six-membered heterocycles 1,3,2-dioxa-, 1,3,2-oxaza-, 1,4,2-dioxa-, and 1,4,2-oxazaphosphepines and 1,3,2- and 1,4,2-dioxaphosphorinanes with a high regio- and stereoselectivity. The hydrolysis and thermolysis of the some benzophosphepine derivatives leads to the substituted fluorinated ketones and various nonphosphorus heterocycles.

The interaction of 2-(5-methyl-2-phenyl-2h-1,2,3-diazaphosphol-4-yl)-4h-benzo[e]-1,3,2-dioxaphosphinin-4-one with activated carbonyl compounds. Synthesis of bis-heterocyclic systems containing di- and tetracoordinated phosphorus

GRAPHICAL ABSTRACT ABSTRACT The interaction of 2-(5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphinin-4-one with mesoxalic and trifluoropyruvic acids ethyl and diethyl esters, hexafluoroacetone and chloral proceeds with an exclusive participation of P(III) atom and allows to obtain 2-(5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-derivatives of 1,4,2- and 1,3,2-dioxaphosphepines as well as dichlorovinylphosphonate, being the product of Perkow reaction in the case of chloral.

Tetracoordinate phosphorus cage compounds with endocyclic P–C bonds: Synthesis and reactivity

The survey summarizes modern methods of synthesis and reactivity of tetracoordinated phosphorus cage compounds containing one or more endocyclic P–C bonds (phosphine oxides, phosphinates and phosphonates, phosphatripticenes and others). Intramolecular cyclization reactions including electrophilic aromatic substitution with unsaturated organophosphorus compounds, reactions of P–H-derivatives with carbonyl compounds as well as cycloaddition reactions involving I–IV-coordinated phosphorus derivatives are considered.

Formation of cage phosphonate via hydrolysis of 2-(5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-1,5-dioxo-4-trifluoromethyl-4-ethoxycarbonylbenzo[f]-1,3,2-dioxaphosphepine

A new approach to obtaining of caged bicyclic phosphonate, 4-hydroxy-3-trifluoromethyl-3-ethoxycarbonyl-8-(1-phenylhydrazonoethyl)-5,6-benzo-2,7,1-dioxaphosphabicyclo[3.2.11.5]octane, based on hydrolysis of 2,5-dioxobenzo[f]1,3,2-dioxaphosphepine derivative bearing 5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl substituent at the phosphorus was developed. The hydrolysis process includes elimination of P(II) atom and intramolecular cyclization involving endocyclic carbonyl group of the phosphepine. Structure of the caged phosphonate was established by NMR and XRD methods.

Features of Reaction of 2-(5-Methyl-2-phenyl-2 H -1,2,3-diazaphosphol-4-yl)-4 H -benzo[ e ]-1,3,2-dioxaphosphorin-4-one with 1,2-Dicarbonyl Compounds

Abstract2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one reacts with perfluorodiacetyl, 3,6-di(tert-butyl)-1,2-benzoquinone and phenanthrenequinone only with the participation of a three-coordinated phosphorus atom to form spirophosphoranes containing acyclic 5-methyl-2- phenyl-2H-1,2,3-diazaphosphol-4-yl substituent, whereas the interaction with tetrachloro-1,2-benzoquinone proceeds via expanding the six-membered heterocycle to the nine-membered one to form 2-(2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-2,9-dioxo-4,5,6,7-tetrachlorodibenzo[d,h]-1,3,8-trioxaphosphonine.

Formation of the P–C and C–C bonds in the Reaction of 2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one with Dimethyl Acetylenedicarboxylate under Mild Conditions

Abstract2-(5-Methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-4H-benzo[e]-1,3,2-dioxaphosphorin-4-one reacts under mild conditions with dimethyl acetylenedicarboxylate with the participation by only threecoordinated phosphorus atom and the formation of 2-(5-methyl-2-phenyl-2H-1,2,3-diazaphosphol-4-yl)-3,4-dimethoxycarbonylbenzo[f]-1,2-oxaphosphepine-2,5-dione. During the process, simultaneous formation of the P–C and C–C bonds takes place.

2-(5-Methyl-2-Phenyl-2H-1,2,3-Dizaphosphol-4-YL)-4H-Benzo[D]-1,3,2-Dioxaphosphorin-4-One in the Synthesis of Bis-Heterocyclic 1,4,2-Oxazaphosphepine Derivatives

GRAPHICAL ABSTRACT Abstract The reaction of 2-(5-methyl-2-phenyl-2H-1,2,3-dizaphosphol-4-yl)-4H-benzo[d]-1,3,2-dioxaphosphorin-4-one with arylimines leads to the formation of seven-membered heterocycles, 3-aryl-2-(5-methyl-2-phenyl-2H-1,2,3-dizaphosphol-4-yl)benzo[f]-1,4,2-oxaza-phosphepin-5-ones with moderate stereoselectivity. 1,2,3-Diazaphospholic moiety does not take part in the process and fulfills the role of sterically hindered substituent.