A General Route to Metal‐Substituted Dipnictenes of the Type [L(X)M]₂E₂

Abstract

Two equivalents of LGa (L=HC[C(Me)N(2,6-iPr C H )] ) reacted with PX (X=Cl, Br) with insertion into two P-X bonds and formation of [L(X)Ga] PX (X=Cl 1, Br 2), whereas the analogous reaction with AsCl occurred with twofold insertion and subsequent elimination of LGaCl and formation of the Ga-substituted diarsene [L(Cl)Ga] As (3). Analogous findings were observed in the reactions with Me NAsCl , yielding the unsymmetrically-substituted diarsene [L(Cl)Ga]As=As[Ga(NMe )L] (4). The reaction of As(NMe ) with LGa gave [L(Me N)Ga] As (5) after heating at 165 °C for five days, whereas the reaction with LAl gave [L(Me N)Al] As (6) after heating at only 80 °C for one day. Finally, two equivalents of LGa reacted with Bi(NEt ) to give [L(Et N)Ga] Bi (7). Complexes 1-7 were characterized by NMR spectroscopy ( H, C, P), elemental analysis, and single-crystal X-ray diffraction (except for 1 and 5). The bonding situations in 4, 6, and 7 were analyzed by quantum chemical calculations.

Syntheses, Structures, and Bonding Analyses of Carbene‐Stabilized Stibinidenes

“…Our interest in reactions of gallanediyl LGa with heavy group 15 element compounds (As, Sb, Bi) resulted in the synthesis of compounds with unusual bonding properties, i.e. Ga‐substituted dipnictenes [L(X)Ga] 2 E 2 (X = halogen, NR 2 , OR), the first Sb analogues of bicyclo[1.1.0]butane [L(X)Ga] 2 Sb 4 (X = halogen, NR 2 ), gallastibenes L(X)GaSbGaL (X = halogen) and ‐arsenes LGaAsCp* (Cp* = C 5 Me 5 ) with Ga‐pnictogen double bonds as well as Sb‐ and Bi‐centered radicals . These reactions were found to occur via (stepwise) insertion of LGa into the pnictogen–X bond and subsequent elimination of LGaX 2 .…”

A General Pathway for the Synthesis of Gallastibenes containing Ga=Sb Double Bonds

“…The formation of 2 , 5 , and 6 can be rationalized by the proposed reaction mechanism as depicted in Scheme . Comparable to the reaction of LGa with PX 3 (X=Cl, Br), the twofold insertion reaction of LGa with SbCl 3 immediately yields [L(Cl)Ga] 2 SbCl 7 , the formation of which was proven by 1 H NMR spectroscopy (Figure S18 in the Supporting Information). 7 shows the same resonance pattern of the two magnetically inequivalent L(Cl)Ga substituents in the 1 H NMR spectrum, as was previously observed for [L(Cl)Ga] 2 PX (X=Cl, Br).…”

“…Synthesis of [L(Cl)Ga] 2 SbCl 7 : LGa (0.2 g, 0.410 mmol) was dissolved in 2 mL of benzene, SbCl 3 (0.047 g, 0.205 mmol) was added and the mixture quickly shaken. The formation of 7 was proven by comparing the 1 H NMR spectrum of 7 , which was recorded immediately after the reagents were combined, with those of [L(Cl)Ga] 2 PX (X=Cl, Br) . Unfortunately, any attempts to isolate a pure sample of 7 failed, to date, due to its strong tendency toward elimination of LGaCl 2 , which can be also seen in the 1 H NMR spectrum of 7 (Figure S18 in Supporting Information).…”

Crystalline Divinyldiarsenes and Cleavage of the As=As Bond

“…[5] Very recently,S chulz and co-workers described an interesting route to access dipnic-tenes (Pn = As or Bi), containingG roup 13 element-derived substituents. [6] Unlike diphosphenes,s tructurally characterized diarsenes however remained limited in number. [2,7] N-Heterocyclic carbenes (NHCs) [8] as well as cyclic (alkyl)(amino)carbenes (CAACs) [9] (Figure 1) are very potent s-donor ligandsa nd have been extensively explored for the stabilization of diatomic main-group species.…”

“…[3] Subsequently, Cowley et al prepared the first stable diarsene RAs=AsR' (R = 2,4,6-tBu 3 C 6 H 2 ,R ' = CH(SiMe 3 ) 2 )i n1 983. [6] Unlike diphosphenes,s tructurally characterized diarsenes however remained limited in number. [5] Very recently,S chulz and co-workers described an interesting route to access dipnic-tenes (Pn = As or Bi), containingG roup 13 element-derived substituents.…”