Marko Kirilov

Di-cyclopentadienyl- und di-indenyl-calcium-komplexe mit ammoniak und tetrahydrofuran

Abstract Dicyclopentadienyl- and diindenyl-calcium and their complexes with twofold coordinated ammonia and tetrahydrofuran are obtained by metalation of cyclopentadiene or indene with calcium or calcium amide in liquid ammonia and subsequent treatment with tetrahydrofuran and heat. IR and 1H NMR spectroscopy are used for structure elucidation. The reactivity of the complexes both in alkylation and in interaction with carbonyl compounds is studied. In this manner alkyl, hydroxyalkyl and alkylidene derivatives of cyclopentadiene and indene axe obtained.

HETEROCYCLIZATION OF 1,2,4- AND 1,3,4-ALKATRIENYLPHOSPHONIC DICHLORIDES WITH ELECTROPHILIC REAGENTS

Abstract By the reaction of 1,2,4- and 1,3,4-alkatrienylphosphonic dichlorides with sulfuryl, sulfenyl and selenenyl chlorides, the different P-containing heterocyclic compounds have been prepared. The obtained heterocycles contained one or two chorine atoms at phosphorus which have great reactivity and can change with another functional groups.

REACTION OF DIMETHYL ESTERS OF 3-METHYL-1,2-ALKADIENEPHOSPHONIC ACIDS WITH METHYLSULFENYL CHLORIDE—ORIENTATION AND STEREOCHEMISTRY

Abstract The reaction of 3-methyl-1,2-alkadienephosphonic acid (i.e.3-alkyl-3-methylsubstituted allenephosphonic) dimethyl esters 1 with methylsulfenyl chloride 2 is oriented mainly to the 1,2-oxaphosphol-3-ene ring products 3a-d (as diastereoisomeric mixtures when alkyl ≠ CH3). In low extent common 1,2-adducts 4a-d as E,Z-mixtures are also formed. The ratio 3:4 and, in particular the E:Z ratio rises by increase of the size of the alkyl group at the allenic C3-atom of 1. Lowering the temperature of the reaction of 1 and 2 leads to an increase of the annulation stereoselectivity although it remains not very high in the studied temperature interval (−45° – +15°C).

5,6-Dihydro-2H-oxaphosphorine-2-oxides by halogenation of 2-chloro-1,3-alkadienylphosphonic dialkyl esters

Abstract Halogenation of 3- and 4-substituted 2-chloro-1,3-alkadienylphosphonic dialkyl esters leads to the formation of six-membered heterocycles derivatives of 5,6-dihydro-2H-1,2-oxaphosphorine-2-oxides. The structure of the products was established by 1H- and 31P-nmr. In one case column chromatography allowed isolation of two diastereomeric six-membered heterocycles without any evidence of formation of non-cyclic or five-membered cyclic products.

REACTION OF LITHIUM DERIVATIVE OF DIETHYL PHENYLMETHANE-PHOSPHONATE WITH KETONES

Abstract The reaction of the lithium derivative of diethyl ester of phenylmethanephosphonic acid (1-Li) with alkanones, cycloalkanones, alkylaryl and diarylketones 2s-b is studied at -70°C in THF. The corresponding adducts-diethyl esters of l-phenyl-2,2-dialkyl(phenyl)-2-hydroxyethanephosphonic acids 3s-h are isolated, their yields being usually higher at short reaction time. The olefination of 3-Li as well as of 3 (both by thermolysis or in acidic media) proceeds in low degree, while in the case of 3-Na the yields of alkenes 4 are good. The relative configurations of 3b. 31 and 3g are determined by IR and NMR-spectra, as well as by their stereospecific olefination. “Threo”-stereoselectivity of the addition stage of the reaction of 1-Li with 2b, 21 and 2g is observed, the “threo”/“erythro” ratio remaining independent on the reaction time.

OLEFIN FORMATION VIA N,N,N′,N′-TETRAMETHYLDIAMIDES OF 1,2-DIARYL-2-HYDROXYETHANEPHOSPHONIC ACIDS IN ACIDIC MEDIA

Abstract The olefin formation via the erythro-N,N,N′N′-tetramethyldiamides of 1,2-diaryl-2-hydroxyethane-phosphonic acids 3, 4 in the presence of aqueous hydrochloric acid proceeds not stereospecifically, while in ethanolic solution of hydrochloric acid (Z)-stereospecific olefin formation predominantly takes place. The mechanism of the elimination process is discussed.

OLEFIN SYNTHESIS VIA THE LITHIUM DERIVATIVES OF THE N,N,N,N′-TETRAMETHYLDIAMIDES OF ARYLMETHANEPHOSPHONIC ACIDS. 2. SYNTHESIS OF SOME (Z)-ORTHO-AND PARA-SUBSTITUTED STILBENES

Abstract The reaction of the lithium derivatives of N,N,N′,N′-tetramethyldiamides of arylmethanephosphonic acids (1-Li) with ortho- and para-substituted benzaldehydes 2 is studied. Reaction conditions are found for erythro-stereoselective addition of 1 to 2 with high diastereomeric purity (95–99%) of the erythro adducts 3, 4 (yields 35–72%). By thermolysis of the adducts in neutral medium the corresponding (Z)-ortho and para-substituted stilbenes 5, 6 are obtained. Some factors causing the predominant formation of the erythro adducts 3, 4, as well as the influence of the ortho-substituents on the equilibrium threo-3, 4 ⇄ erythro-3, 4 are discussed.

REACTION OF THE LITHIUM DERIVATIVE OF DIETHYL 2-(OR 3-)METHYLPHENYLMETHANEPHOSPHONATE WITH KETONES. AN EXAMPLE OF HIGH SYN-STEREOSELECTIVITY

Abstract The reaction of the lithium derivative of diethyl ester of 2-(or 3-)methylphenylmethanephosphonic acid (1-Li) with a large number of symmetric and unsymmetric ketones 2a-r is studied at −70°C in THF, the corresponding adducts—diethyl esters of 1-(2- or 3-methylphenyl)-2,2-dialkyl(phenyl)-2-hydroxy-ethanephosphonic acid 3a-r being isolated. The results of stereospecific olefination of the β-hydroxyphosphonates 3j, 3k, 3o and 3p indicate the influence of combined steric effects in ketones 2 and ortho- and metha-methyl substituted benzylphosphonates 1. Spectral investigations and PM3-calculations prove high synstereoselectivity of the reaction of ortho-methyl substituted benzylphosphonates 1a with studied ketones.

OLEFIN SYNTHESIS VIA THE LITHIUM DERIVATIVE OF THE N,N,N′,N′-TETRAMETHYLDIAMIDES OF ARYLMETHANEPHOSPHONIC ACIDS. 3 SYNTHESIS OF SOME β-DISUBSTITUTED STYRENES

Abstract The reaction of Li-derivatives of N,N,N′,N′-tetramethyldiamides of arylmethanephosphonic acids (1-Li) with alkanones, cycloalkanones, alkylaryl-and diarylketones 2a-h is studied. It is found that in THF at-70°C adducts 3-Li and 4-Li are formed, the corresponding hydroxyl compounds 3 and 4 being isolated in 36–81% yields, while by elevated temperatures the reaction is completely shifted to the starting 1-Li and 2. By thermolysis of 3 and 4 in neutral medium olefins 5 and 6 are obtained even from readily enolysable ketones. The stereochemistry of the addition reaction with nonsymmetrical ketones as well as the influence of the substituents at the carbonyl groups on the conformation and adsorption properties of the adducts are discussed.

Untersuchungen über die Tautomerie von Dialkylestern der 1-Cyano-2-oxo-alkanphosphonsäuren durch die Methode der σϱ-Analyse und die LCAO-MO-Methode

The applicability of the principle of linear free energies to the tautomerism of dialkyl esters of 1-cyano-2-oxo-alkanephosphonic acids is studied. Correlations between the tautomeric equilibrium constants andTafts inductive constants, as well asKabachniksσϕ constants of the substituents in RO-groups at the phosphorus atom and those at the carbonyl group in some series of compounds of this type are found. The dominating inductive influence of the R-substituents on the position of tautomeric equilibrium in these compounds is proved also by model quantum chemical investigation of the effects of conjugation in the corresponding tautomeric forms byHückels LCAO—MO-method.