The conjugated bis-guanidinate (CBG) supported zinc hydride, [{LZnH} 2 ; L = {(ArHN)(ArN)-C�N−C�(NAr)-(NHAr); Ar = 2,6-Et 2 -C 6 H 3 }] (1) (pre)-catalyzed addition of E− H (E = B, C, N, and O) to carbodiimides is presented. Compound 1 catalyzed the reduction of carbodiimides with pinacolborane (HBpin), terminal alkynes, primary amines, and alcohols, gave a series of N-boryl formamidines, propiolamidines, guanidines, and isoureas with high conversions. All these reactions display good tolerance of functional groups. These reactions proceeded through the active catalysts and intermediate of zinc amidinate (Zn-1, Zn-1′, and Zn-3), zinc alkynyl (Zn-2, and Zn-2′), zinc anilide (Zn-4), and zinc alkoxide (Zn-5) complexes, which have been characterized by multinuclear NMR and HRMS analyses. Moreover, compounds Zn-1′, Zn-2′, Zn-4, and Zn-5 were confirmed by singlecrystal X-ray diffraction studies. Complete catalytic cycles have been proposed based on well-defined intermediates and stoichiometric experiments.

This review deals with advances in the chemistry of organic isocyanide complexes of the main group metals. Isocyanides acting as functional groups show a great dichotomy between nucleophilic and electrophilic characters, which diversifies the course of different multicomponent reactions. The carbon and nitrogen centers can serve as the donor atom in different metal isocyanide frameworks. Along with the variation in ligation properties and different coordination modes, the metalated isocyanides emerge as a well-established organometallic system with an effective synergistic mechanism, making them chemically and synthetically significant to chemists. However, the linear arrangement of the MÀ C=NÀ R induces the formation of multinuclear isocyanide complexes of good thermal stability, which draws the metalated isocyanides into the focal point of advanced reactivity and catalytic studies. A thorough literature survey on molecular main group metal complexes with organic isocyanides has been provided.

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A new example of structurally characterized conjugated bis-guanidinate (CBG) supported zinc (I) dimer, i.e., LZnZnL (3) (L = {(ArNH)(ArN)–C=N–C=(NAr)(NHAr)}; Ar = 2,6-Et2-C6H3)) with a Zn-Zn bond is reported. Moreover, homoleptic...