Übergangsmetall‐substituierte Diphosphene. 37 [1]. Spaltung der PBindung im Metallodiphosphen (η⁵‐C₅Me₅)(CO)₂FePPMes* (Mes* = 2,4,6‐tBu₃C₆H₂) durch Alkylisocyanide. Strukturbestimmung von (η⁵‐C₅Me₅)(CO)₂FeP(NHCH₂C₆H₅)C(NHCH₂C₆H₅)PMes*

Abstract

Die Reaktion des Metallodiphosphens (η5‐C5Me5)(CO)2FePPMes* (1) mit zwei Äquivalenten Cyclohexylisocyanid (2 a) bzw. Benzylisocyanid (2 b) liefert (E/Z)‐Gemische der 2,4‐Diimino‐1,3‐diphosphetane (η5‐C5Me5)(CO)2Fe=NR (3 a: R = c‐C6H11; 3 b: R = CH2C5H5). Komplex 1 reagiert mit einem Äquivalent Benzylisocyanid in Benzylamin als Lösungsmittel zu dem 3‐Metallo‐1,3‐diphosphapropen (η5‐C5Me5)(CO)2FeP · (NHCH2C6H5)C(NHCH2C6H5)=PMes* (4). Konstitution und Konfiguration der Verbindungen 3 a, b, 4 wurden durch Elementaranalysen und Spektren (IR, 1H, 13C, 31P‐NMR, MS) ermittelt. Von 4 wurde zusätzlich eine Einkristall‐Röntgenstrukturanalyse durchgeführt.

Phosphaazaallene Dimerization and Phosphaallene Isomerization: Catalysis by Zerovalent Palladium and Platinum Complexes

“…The 31 P{ 1 H} NMR spectrum shows one peak at 10 ppm and the 13 C{ 1 H} NMR spectrum a triplet ( 1 J P - C = 30 Hz, CNPh) at δ 181.9. The IR spectrum exhibits bands at 1543 and 1585 cm -1 (ν CN ), which are comparable to those reported for related dimers 2 …”

“…Signals corresponding to the unsaturated carbons appear in the 13 C{ 1 H} NMR spectrum at δ 173.3 (dd, 1 J P - C = 96 Hz, 3 J P - C = 14 Hz) and at δ 164.3 (dd, 1 J P - C = 28 Hz, 3 J P - C = 17 Hz). The IR spectrum shows a band at 1585 cm -1 which can be assigned to the CN stretch …”

“…This compound forms both orthorhombic and monoclinic crystals, in which the ring P−C bond lengths range from 1.838(16) to 1.796(5) Å, with CPC bond angles of 84.1(7) and 81.7(3)° and PCP angles ranging from 98.3(3) to 94.9(8)°. Several heterocycles [RP(μ-CNR‘)] 2 analogous to 7 but with other, usually sterically less demanding substituents, have been prepared and crystallographically characterized, and their structures are similar to that of 7 . 5b,d …”

Four-membered rings from isocyanides: Developments since the mid 1980s

“…17 Threemembered rings like 24c,d were also isolated when the metal-substituted diphosphene 23b was reacted with phenyl or trifluoromethyl isocyanide; the same holds for the reaction of the latter component with the analogous substrate (23c  24e). 18 However, treatment of 23c with several aryl 18 and alkyl isocyanides 19 led directly to 1,3-diphosphetanediimines like 25a-f; the transient compounds 24f-k, being prone to P-P fission (cf. Section 3.1), were detected spectroscopically.…”