2,4-Dimethoxycarbonyl-1,1,3,3-tetrakis(dimethylamino)-1λ5,3λ5-diphosphete

1,1,3,3 - Tetrakis(dimethylamino) - 1λ⁵,3λ⁵ - diphosphete, 1 , reacts with cyanoformic acid methyl ester to form two isomers of the title compound 2 . Properties, NMR, mass, and IR spectra of 2 , as well as the molecular and crystal structure of the E isomer of 2 , are described and discussed.     

Synthese,Eigenschaften und NMR-spektroskopische Untersuchungen an 2,4-Dithioxo-2,4-dimercapto-1,3-diaza-2λ5,4λ5-diphosphetidinen

Synthesis, Properties and N.M.R. Spectroscopic Studies of 2,4-Dithioxo-2,4-dimercapto-1,3-diaza-2λ⁵,4λ⁵-diphosphetidines On the reaction of py · PS₂Cl ( 1 ) or py · PS₂F ( 2 ) (py = Pyridine) with hexamethyl disilazane in a molar ratio of 1:1 the pyridinium salt of the 1,3-bis(trimethylsilyl)-2,4-dimercapto-2,4-dithioxo-1,3-diaza-2λ⁵, 4λ⁵-diphosphetidine ( 3 ) is formed. 3 reacts with MeI to the corresponding methyl ester 9 . There exist two isomers of 9 , probable with cis and trans configuration of the MeS groups, respectively. 3 and 9 have been characterized by i.r., Raman, mass, and NMR spectroscopy. 4 reacts in acetonitrilic solution in the presence of water under hydrolytic cleavage of the trimethyl silyl groups whereas the P₂N₂ ring is preserved. The hydrolysis of 9 has been studied by ¹H-, ³¹P-, and ¹³C-NMR spectroscopy.     

A 1,5-diaza-2,4-(λ4P+, λ6P−)-diphosphorinane

The oxidation of the 1,3-diaza-4,6-diphosphorine 1 with tetrachloroorthobenzoquinone 2 led, unexpectedly, to the formation of 1,5-dimethyl-2,2-bis(dimethyl-amino)-4,4,4,4-bis-(tetrachloro-o-phenylenedioxa)-1,5-diaza-2,4-λ⁴, λ⁶-diphosphorinane-6-one 4 , containing two phosphorus atoms of opposite formal charge and different coordination number. The X-ray crystal structure analysis of 4 revealed the presence of a six-membered ring with an unusual conformation.     

Synthese und NMR-Spektren von λ5-Diphospheten Die Struktur des 2,4-Diphenyl-1,1,3,3-tetrakis(diethylamino)-1λ5,3λ5-diphosphets

Synthesis and NMR Spectra of λ⁵-Diphosphets. Structure of 2,4-Diphenyl-1,1,3,3-tetrakis (diethylamino)-1λ⁵, 3λ⁵-diphosphete Preparation, properties, and n.m.r. spectra of C₂H₅PF₂[N(C₂H₅)₂]₂, CH₂?PF[N(C₂H₅)₂]₂, and the diphosphetes {RC?P[N(C₂H₅)₂]₂}₂ (R) ? H ( 5a ), CH₃ [( 5b )] are described. The λ⁵-diphosphete {HC?P(NR₂)₂}₂ (R ? CH₃) reacts with BF₃ · O(C₂H₅)₂ to give which is transformed into by n-C₄H₉Li. The crystal and molecular structure of 2,4-diphenyl-1,3,3-tetrakis(diethylamino)-1λ⁵,3λ⁵-diphosphete 2 are reported and discussed.     

1λ5,3λ5-Diphospholium ions

One example each is given for the reaction of bromoacetylenes and ethynyl-phenyliodonium tosylates with bis(diphenyl phosphino)methane. The yellow crystalline 1:1-addition products are diphospholium salts. They readily and selectively hydrolyze to give 2-phosphinoylethenyl phosphonium salts.     

1,2λ5,5λ5-azadiphospholium structures

The reactions of bromophenylacetylene with the diphenylphosphino amines (Ph₂P)₂NH and (Ph₂P)₃N result in the 1,1,3,3,4-pentaphenyl-1,2,5-azadiphospholium bromide ( 5 ) and its 4-diphenylphosphino derivative ( 7 ). Their X-ray structure analyses show planar rings for the cations. The small endocyclic angle at the nitrogen ring member is associated with PN bonds that are longer than in the acyclic cation (Ph₃P)₂N⁺. The data fit to a negative linear relationship of PN bond lengths and PNP bond angles. © 1997 John Wiley & Sons, Inc.     

Mono- und Bis(difluorphosphoranyl)ethylen,n-Hexyliden-fluorphosphoran und ein 2,4-Di-n-pentyl-1λ5,3λ5-diphosphet

Mono- and Bis(difluorophosphoranyl)ethylene, n-Hexylidene-fluorophosphorane, and a 2,4-Di-n-pentyl-1λ⁵, 3λ⁵ -diphosphete Bis(diethylamino)phosphanylethylene, 1 , is converted by SF₄ into bis(diethylamino)difluorophosphoranylethylene, 2. Analogously trans-1,2-bis(diphenylphosphanyl)ethylene, 3 , is converted into trans-1,2-bis(difluorodiphenylphoranyl)ethylene, 4. 2 reacts with n-butyllithium to give n-hexylidene-bis(diethylamino)fluorophosphorane, 5. With more n-butyllithium, the main product n-hexylidene-bis(diethylamino)-n-butylphosphorane, 7 , and the by-product 2,4-di-n-pentyl-1,1,3,3-tetrakis(diethylamino)-1λ⁵, 3λ⁵ -diphosphete, 8 , are formed. With t-butyllithium 2 yields 3,3-dimethyl-butylidene-bis(diethylamino)fluorophosphorane, 6. All new compounds 1, 2, 4–8 are characterized by their nmr and ir spectra.