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Organophosphorus compounds containing a functional group in the a-position of the alkyl radical are of great interest in both theoretical fundamental investigations and for practical applications. Functionally substituted methyl-phosphonites and their derivatives, belonging to this broad class of organophosphorus compounds, are convenient objects for investigating mutual effects of trivalent phosphorus and a heteroatom, or functional groups attached to it in the a-position. They have also become key substances in obtaining new organophosphorus compounds. Functionally sub-stituted compounds of tetracoordinated phosphorus have been intensively investigated in recent years; rather convenient methods of synthesis of these compounds have been proposed and their properties have been studied in detail1. However, the corresponding compounds of tricoordinated phosphorus are not available or difficult to obtain. Recently we re-ported on the properties of halogen-substituted methylphos-phines and their deri...

Element-substituted acylphosphines are stable in form 2 R1P(ERn)COR2 (A), when E=Ge, Sn, Sb, P, T1 and in form R1 P=C(OERn)R2 by NMR data. The reaction

Organophosphorus compounds containing a functional group in the a-position of the alkyl radical are of great interest in both theoretical fundamental investigations and for practical applications. Functionally substituted methyl-phosphonites and their derivatives, belonging to this broad class of organophosphorus compounds, are convenient objects for investigating mutual effects of trivalent phosphorus and a heteroatom, or functional groups attached to it in the a-position. They have also become key substances in obtaining new organophosphorus compounds. Functionally sub-stituted compounds of tetracoordinated phosphorus have been intensively investigated in recent years; rather convenient methods of synthesis of these compounds have been proposed and their properties have been studied in detail1. However, the corresponding compounds of tricoordinated phosphorus are not available or difficult to obtain. Recently we re-ported on the properties of halogen-substituted methylphos-phines and their deri...

Addition of variousnucleophiles to phosphaalkenes is considered to be irreversible. As an example, the quantitative formation of iminodiphosphine III from phosphinous amide and phosphaalkene was recently reported (1).

Dialkylaminomethylation of trimethylsilyl esters of trivalent phosphorus acids using bis(dialkylamino)methanes was carried out for the first time. This reaction is a convenient method for preparation of quaternary coordinated phosphorus compounds, including dialkylaminomethyl and functional groups. Thus trimethylsilylphosphites and -phosphonites of various structures react with bis(dialklamino)-methanes according to Arbuzov reaction in the presence of zinc chloride as a catalyst, when heated to 120°C, resulting in formation of phosphonates and phosphinates (I)

Element-substituted acylphosphines are stable in form 2 R1P(ERn)COR2 (A), when E=Ge, Sn, Sb, P, T1 and in form R1 P=C(OERn)R2 by NMR data. The reaction

A number of organoantimony aliphatic-aromatic ketones have been synthesized. Spatial effects are more important than electronic effects in stabilising the O -species in the tautomeric mixtures.

The three isomers possible for oxidized 1,1-dialkyl-2,2-dialkoxydiphosphines, R2(O)P–P(OR')2 1, R2P–O–P(OR')2 2, and R2P–P(O)(OR')2 3, have been synthesized. Irreversible transformations of 1 to 2 and 2 to 3 have been found and the rearrangement patterns, the role of electrophilic and nucleophilic catalysts are discussed. The fact that 3 is more stable than 1 is attributed to higher donor activity of the ligands attached to the four-coordinate phosphorus in 3. Acid chlorides have been shown to attack the phosphorus atom of ambident anions of trivalent phosphorus acids (the products are 1 and 3) whereas the acids proper react with the acid halides at the oxygen atom, to give 2.

The past two decades have brought us a snowballing development of organophosphorus chemistry. Indeed organophosphorus compounds have found wide practical application (in agriculture, petroleum industry, as drugs, etc.) and continue to afford promising objects for the study of theoretical matters such as tautomerism, ambiphilicity, ambidenticity, and other problems of organic chemistry. On the other hand, however impressive this progress may be, the search for new methods of synthesis, improving the known methods and forecasting new types of organophosphorus compounds remain as challenging problems as before.

Data on the methods of synthesis and reactivities of organic diphosphines with a direct P–P bond between four-coordinated phosphorus atoms as well as compounds with a P–P bond between a three-coordinated phosphorus atom and a phosphorus atom with a higher degree of coordination are surveyed and described systematically. Problems of the steric structures and the results of structural analysis, spectroscopic studies, and studies by other methods are considered. The bibliography includes 269 references.

The alkylation and acylation reactions of dialkoxymethylphosphonites and their analogues have been studied. The Arbuzov rearrangement of these compounds was accompanied by the P[sbnd]C bond cleavage with retention of three-coordinate phosphorus atom.

A number of organoantimony aldehydes and ketones have been synthesised. An increase in the spatial hindrance at either the α-carbon or the antimony increases the O -isomer relative content.

In a study of the interaction of ketene with mono- or dialkylaminosilanes a number of new rearrangements was observed. When acted upon by ketene, dialkylaminosilanes, depending on the conditions applied, produce either amides of β-siloxyvinylacetic acid (I) (route “a”, scheme A) or amides of silylated acetic acid (II) (routes “b”, “c”). In both cases an intermediate α-siloxyvinyldialkylamine (III) was isolated which may be rearranged to give amide (II). N-Trialkylsilyl-N-alkylacetamides (IV) are obtained both through the interaction of ketene with N-alkylsilylamines (route “d”, scheme B) and a thermal rearrangement of N-alkylamides of silylated acetic acid (VII) (route “e”). Further action of ketene on amides (IV) may lead to N-alkyl-α-siloxyvinylacetamides (V) (route “g”). Amides (IV) react with trialkylsilylacetyl chloride (VIII) yielding an acylated N-alkylamide of trialkylsilylacetic acid (VI), thermal isomerisation of the latter leading to the analogues of (V) (route “k”). This rearrangement is interesting in that its direction is the reverse of that of a reaction studied earlier—the isomerisation of O-methyl-O-silylketeneacetals to esters of silylated acetic acid—and it enables the factors that have a decisive influence on such rearrangements to be more closely studied.

1. By the addition of mercuric acetate to vinyl ether, mercurated acylals of the following general formula were prepared: 2. By an investigation of the chemical behavior of the mercurated acylals it was established that they have dual reactivity. 3. Bromo acylals of the following formula were synthesized: R=C2H21−C3H2, C4H3.

1. The conditions of dual reactivity of the esters of α-metalated carboxylic acids with the halides of some organosilicon compounds were examined. 2. The rearrangement of O -silyl- O -alkylketeneacetals into esters of silylacetic acid is reported.

1. The products of the reactions ofα-metallized aldehydes, ketones, and esters of carboxylic acids with halides, hydrides, and sulfides of groups IV and V of the Periodic System were studied by the PMR method. Their C- (types 1 and 3) and O- (type 2) structure was established: 2. The inductive influence of substituents directly bonded to the phosphorus atom was studied. The change in the parameters of the PMR spectra of acetonyl derivatives of tri- and pentavalent phosphorus is of the same type. The differences in the valence state of the phosphorus atom, as well as the replacement of oxygen by sulfur, have no effect upon the parameters of the PMR spectra. Substituents are arranged in the following order with respect to influence on the chemical shift of the methylene protons: Cl > C6H5 > OAlk > Alk. 3. A comparison of the PMR data on the derivatives of tri- and pentavalent phosphorus containing the isopropenyloxy group gives a series of influence of substituents differing from that cited above: Cl > OAlk > C6H5 > Alk. 4. For derivatives of phosphonous and phosphinous acids, containing a carbalkoxymethyl group at the phosphorus atom, the change in the chemical shifts of the protons of the methylene group is correlated with the change in the inductive effect of the substituent at the phosphorus atom, while no obvious patterns are observed in the change of the spin-spin interaction constants JP-C-H.

1. It was shown that arylmercury hydroxides do not react with unsaturated hydrocarbons. 2. Arylmercury hydroxides react with vinyl ethers with formation of the diarylmercury together with mercuridiacetaldehyde or a mercuridialkanone. The reaction can be applied as a new method for the symmetrization of organomercury salts under mild conditions. It gives almost quantitative yields of diarylmercury. 3. Arylmercury hydroxides readily react with ketene diethyl acetal with formation of the diarylmercury and mercurated ethyl acetate.

A number of germylated alkyl acetates have been synthesized by the reaction of halogermanes with alkyl (trialkylstannyl)acetates and the reaction of alkoxygermane with ketene. It has been assumed that, in the last case, the reaction proceeds through an intermediate keteneacetal derivative.

1. A method is proposed for the synthesis of acetals of mercurated acetaldehyde from vinyl ethers and esters. 2. It is shown that, in their reactions, mercurated acetals are in many ways reminiscent of the addition products formed by mercury salts with olefins.

Kinetically controlled interaction of (R 1 PCOR 2 )Li with R 3 SiCl in nonsolvating media gives P -silylated acylphosphines, which rearrange to O-E isomers. Direct formation of O-Z isomers was observed in solvating media with R 2 BX and R 3 SiX. Equilibria of E/Z isomers exist for B- or Si-derivatives of isobutyrylphosphines. Both isomers rearrange irreversibly to vinylphosphines.

Eine Arbusovumlagerung dieser Ester, z.B. (I) und (III), kann je nach Reaktionsbedingungen und Struktur der Alkylhalogenide an einem oder beiden P-Atomen stattfinden.

The reaction of trialkylsilyl- and trialkylgermyl-ketenes with trialkylsilyldiazomethanes proceeds stereoselectively to give one of two feasible stereoisomers, the Z -2,3-bis(Si,Ge)-substituted cyclopropanone. The addition of nucleophilic reagents such as benzyl alcohol, LiAlH 4 or (trimethylsilyl)dialkylphosphites is highly stereoselective and is a convenient method for assigning the stereochemical configuration of 2,3-substituted cyclopropanones.