Acyl‐ und Alkylidenphosphane. XXV. Molekül‐ und Kristallstruktur des 1,2‐Di(tert‐butyl)‐3‐dimethylamino‐1‐thio‐4‐trimethylsilylsulfano‐1λ5,2λ3‐diphosphet‐3‐ens

Becker, Gerd; Becker, W.; Uhl, G.

doi:10.1002/zaac.19845191204

Cited by 9 publications

(1 citation statement)

References 31 publications

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“…This is also the case for the P1−O bond length [1.482(2) Å]. However, the difference in lengths of almost 0.10 Å between the two cyclic P−C bonds is worthy of note [P1−C4, 1.753(3) Å; P2−C3, 1.849(3) Å]; even though comparable values have previously been reported for a 1-thio-1,2-dihydro-1λ 5 ,2λ 5 -diphosphete …”

Section: Resultssupporting

confidence: 72%

Phosphaalkenes as Building Blocks in Ene Reactions: Synthesis and Reactivity of 3-Amino-1,2-dihydro-1,2-diphosphetes

et al. 1997

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Phospha-ene reactions of the type II between methylidenephosphanes as enophiles and Caminophosphaalkenes possessing allylic hydrogen atoms proceed by P-P bond formation to furnish the corresponding functionalized diphosphanes. Thus, the reaction of the methylidenephosphane 1 with the C-amino-substituted ethylidenephosphane 3a runs smoothly at room temperature to afford the unsymmetrical 1,2-diphosphane 4 as a 60:40 mixture of two diastereomers in 64% yield. Rotation about the P-N bond in 4 is hindered at room temperature, but free enthalpies of activation of ∆G q (PN) ) 16.3 kcal‚mol -1 (major diastereomer) and 15.2 kcal‚mol -1 (minor diastereomer) were determined by variable temperature 1 H NMR spectroscopy. In contrast, reactions of the ethylidenephosphanes 3a-c with the chlorophosphane 2 as enophile follow an unusual course involving a regiospecific ene reaction of the type II and a subsequent intramolecular ring closure reaction to furnish the 3-amino-1,2-dihydro-1,2-diphosphetes 7a-c in good yields (53-79%). The reactivity of this new class of heterocyclic compounds has been studied exemplarily for product 7a. The trans form of 7a obtained by synthesis can be converted to the corresponding cis form photochemically. Complexation of both phosphorus centers in 7a is possible by reaction with 2 equiv of diiron nonacarbonyl and gives rise to complex 8, the constitution of which has been confirmed by X-ray crystallography. Unexpectedly, hydrolysis of 7a does not proceed by attack at the endocyclic enamine unit but rather by way of P-P bond cleavage to afford the functionalized phosphaalkene 9. On the other hand, oxidation of 7a by bis(trimethylsilyl) peroxide takes place with retention of the P 2 C 2 skeleton: a selective increase in coordination at P-1 results in the formation of the 1-oxo-1,2-dihydrodiphosphete 10, the structure of which was confirmed by X-ray crystallography. The reactions of 7a with the electron-poor acetylenes 11a-d also follow an unusual course. Nucleophilic attack of P-1 at the CtC triple bond and proton shift lead stereospecifically to the 1-methylene-1,2-dihydro-1,2-diphosphetes 12a-d as thermolabile addition products. The constitution and configuration of 12c were unambiguously confirmed by X-ray crystallography.

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Section: Resultssupporting

confidence: 72%

Phosphaalkenes as Building Blocks in Ene Reactions: Synthesis and Reactivity of 3-Amino-1,2-dihydro-1,2-diphosphetes

et al. 1997

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ChemInform Abstract: ACYL‐ AND ALKYLIDENEPHOSPHINES. XXV. MOLECULAR AND CRYSTAL STRUCTURE OF 1,2‐DI‐TERT‐BUTYL‐3‐(DIMETHYLAMINO)‐1‐THIOXO‐4‐(TRIMETHYLSILYLTHIO)‐1Λ5, 2Λ3‐DIPHOSPHET‐3‐ENE

Becker¹,

Becker²,

Uhl³

1985

Chemischer Informationsdienst

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Acyl‐ und Alkylidenphosphane. XXVI. 2, 4‐Bis(phenylimino)‐1,3‐diphosphetane aus Thiocarbamoyl‐ und Carbamoyltrimethylsilylphosphanen

Becker

Härer

Uhl

et al. 1985

Zeitschrift anorg allge chemie

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Die Bis(trimethylsilyl)phosphane RP[Si(CH3)3]3 1 (R=H5C6 b, H3C)3C c, H11C9 d) reagieren mit Phenylisothiocyanat zu Insertionsverbindungen, die sowohl in Lösung als auch im Festkörper [2] als [(N‐Phenyl‐Derivat 3−2beliminiert in Gegenwart geringer Menge an festem Katalysators Bis(trimethylsilyl] sulfan; dei zunächst gebildeten, instabilen [(Phenylimino)‐methyliden]phosphane 6 dimerisieren rasch zu den in Lösung E/Z‐isomeren 2, 4‐Bis (phenylimino)‐1, 3‐diphosphetanen 7. Diese cyclischen Phosphane 7 sind über die NaOH‐katalysierte Abspaltung von Hexamethyldisiloxan auch aus den Addukten 2 des Phenylisocyanats an Bis(trimethylsilyl)‐phosphane 1zugänglich. Die Temperaturabhängigkeit de NMR‐Spektren wird am Beispiel des thermisch hinreichend stabilen tert‐Butyl‐Derivates 7c eingehend untersucht.

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Acyl‐ und Alkylidenphosphane. XXV. Molekül‐ und Kristallstruktur des 1,2‐Di(tert‐butyl)‐3‐dimethylamino‐1‐thio‐4‐trimethylsilylsulfano‐1λ⁵,2λ³‐diphosphet‐3‐ens

Cited by 9 publications

References 31 publications

Phosphaalkenes as Building Blocks in Ene Reactions: Synthesis and Reactivity of 3-Amino-1,2-dihydro-1,2-diphosphetes

Phosphaalkenes as Building Blocks in Ene Reactions: Synthesis and Reactivity of 3-Amino-1,2-dihydro-1,2-diphosphetes

ChemInform Abstract: ACYL‐ AND ALKYLIDENEPHOSPHINES. XXV. MOLECULAR AND CRYSTAL STRUCTURE OF 1,2‐DI‐TERT‐BUTYL‐3‐(DIMETHYLAMINO)‐1‐THIOXO‐4‐(TRIMETHYLSILYLTHIO)‐1Λ5, 2Λ3‐DIPHOSPHET‐3‐ENE

Acyl‐ und Alkylidenphosphane. XXVI. 2, 4‐Bis(phenylimino)‐1,3‐diphosphetane aus Thiocarbamoyl‐ und Carbamoyltrimethylsilylphosphanen

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