Untitled

Abstract

Diphosphabenzole. VII [1]Reaktionen von 1,1,3,3-Tetrakis(dimethylamino)-1 k 5 , 3 k 5 -diphosphet mit 5-Cyano-1-pentin und mit 2-(Cyanmethyl)-1-methylpyrrol Inhaltsu È bersicht. 5-Cyano-1-pentin reagiert mit der a È quimolaren Menge des k 5 -Diphosphets 1 zum k 5 -Diphosphinin (k 5 -Diphosphabenzol) (3), mit der doppelt a È quimolaren Menge 1 zum k 5 -Diphosphinin (4). 2-(Cyanmethyl)-1-methylpyrrol (5) bildet mit 1 als Hauptprodukt die acyclische Verbindung 6. Die Schmelzpunkte von 4´CH 3 CN und 6 sowie die Massen-, NMR-und IR-Spektren von 3, 4 und 6 werden mitgeteilt. Die Kristallstruktur von 4´CH 3 CN zeigt eine offenkettige ylidische CPCP-Sequenz, die mit dem sechsgliedrigen Heterocyclus eines k 5 -Diphosphinins u È ber eine Ethylenbru È cke verknu È pft ist. Die Kristallstruktur von 6 besta È tigt das Vorliegen eines acyclischen konjugierten Doppelylids. Diphosphabenzenes. VII.Reactions of 1,1,3,3-Tetrakis(dimethylamino)-1 k 5 , 3 k 5 -diphosphete with 5-Cyano-1-pentine and 2-(Cyanomethyl)-1-methylpyrrol Abstract. 5-Cyano-1-pentine reacts with the equimolar amount of the k 5 -diphosphete 1 to give the k 5 -diphosphinine (k 5 -diphosphabenzene) (3), while reaction with the double equimolar amount of 1 yields the k 5 -diphosphinine (4). The acyclic compount 6 is the main product of the reaction between 1 and 2-(cyanomethyl)-1-methylpyrrol, 5. Melting points of 4´CH 3 CN and 6, and mass, nmr and ir spectra of 3, 4, and 6 are reported. The crystal structure of 4´CH 3 CN shows an open-chain ylidic CPCP-sequence, which is linked to a k 5 -diphosphinine via an ethylene bridge. The X-ray structure analysis of 6 confirms the existence as an acyclic conjugated double ylid.Keywords: 1 k 5 ,3 k 5 -diphosphete; 1 k 5 ,3 k 5 -[1,3]diphosphinine; 3,5-diphospha-hexa-2,4-diene nitrile; n.m.r, i.r. spectroscopy; Crystal structure.

Synthesis and Properties of Phosphorus Ylides Containing Fluorine Atoms Bonded to Phosphorus

“…38 The carbodiphosphoranes 21 were obtained by reaction of bis(difluorophosphorany1)methane 20 with butyllithium (Scheme 15). The structure of the carbodiphosphorane 21 was determined by X-ray crystallo- graphy.…”

“…20 It was reported that the reaction of bis(difluorophosphoranyl)ethane with butyllithium furnishes the bis-ylide in good yield. 38 The carbodiphosphoranes 21 were obtained by reaction of bis(difluorophosphorany1)methane 20 with butyllithium (Scheme 15). The structure of the carbodiphosphorane 21 was determined by X-ray crystallo-Table 1 Characteristic Data of P-Fluoro Ylides 1 a) CR 3 R 4 = graphy.…”

“…The structure of the carbodiphosphorane 21 was determined by X-ray crystallo-Table 1 Characteristic Data of P-Fluoro Ylides 1 a) CR 3 R 4 = graphy. 30,38 The symmetrical P-fluorosubstituted carbodiphosphoranes 21 were also prepared by dechlorination of the halophosphonium salts 22 with tris(dimethylamino)phosphine (Scheme 16, Method D). [39][40][41] Scheme 15 R = Ph (a), Me 2 N (b)…”