Reactivity of a Lewis Base Supported Thorium Terminal Imido Metallocene toward Small Organic Molecules

The Lewis base supported thorium terminal imido metallocene (η5-C5Me5)2ThN­(mesityl)­(DMAP) (1) reacts with various small organic molecules such as thiazoles, silanes, internal acetylenes, nitriles, ketones, CS2, isothiocyanates, carbodiimides, lactides, organic azides, and diazoalkane derivatives. For example, while 1 forms the adduct (η5-C5Me5)2ThN­(mesityl)­(OPPh3) (2) with Ph3PO, deprotonation occurs between 1 and thiazole to give the amido thiazolyl complex (η5-C5Me5)2Th­(NHmesityl)­(C3H2NS) (3). Moreover, the five-membered metallaheterocycle (η5-C5Me5)2Th­[κ2-N,C-{N­(2-CH2-4,6-Me2C6H2)­(SiH2Ph)}]­(DMAP) (4) is isolated from a mixture of 1 and PhSiH3. In addition, treatment of 1 with PhCN, Ph2CHCN, or Me3SiCN gives the zwitterionic complex (η5-C5Me5)2Th­[κ-N-{NCPh­(N­(mesityl))}]­(DMAP) (5), and iminato compounds (η5-C5Me5)2Th­[N­(mesityl)­C­(CHPh2)­NH]­(NCCPh2) (6) and (η5-C5Me5)2Th­[2-{NC­(SiMe3)}-4-Me2NC5H3N]­(NC) (7), respectively. Furthermore, reaction of 1 with PhCCMe and Me3SiCCCCSiMe3 afford the amido pyridyl complexes (η5-C5Me5)2Th­[N­(mesityl)­C­(Me)CHPh]­(κ2-C,N-4-Me2NC5H3N) (8) and (η5-C5Me5)2Th­[N­(mesityl)­C­(C2SiMe3)CHSiMe3]­(κ2-C,N-4-Me2NC5H3N) (9), respectively. Treatment of 1 with N,N′-diisopropylcarbodiimide furnishes the [2 + 2] cycloaddition product (η5-C5Me5)2Th­[N­(mesityl)­C­(N i Pr)-N i Pr]­(DMAP) (10), whereas reaction of 1 with CS2 or PhNCS affords the four-membered metallaheterocycles (η5-C5Me5)2Th­[SCN­(mesityl)-S]­(DMAP) (11) and (η5-C5Me5)2Th­[SCN­(mesityl)-NPh]­(DMAP) (12), respectively. Moreover, while the four-membered metallaheterocycle (η5-C5Me5)2Th­[(μ-O)2(CPh2)]­(DMAP) (13) is formed upon addition of Ph2CO to 1, deprotonation occurs between 1 and 1-indanone to give the amido enolyl compound (η5-C5Me5)2Th­(NH­(mesityl))­(κ-O-1-OC9H7) (14). Nevertheless, the eight-membered metallaheterocycle (η5-C5Me5)2Th­[OCH­(Me)­C­(O)­OCH­(Me)­C­(N­(mesityl))­O] (15) is isolated from reaction of 1 with rac-lactide. Furthermore, while mixing 1 with (p-tolyl)­N3 affords the tetraazametallacyclopentene (η5-C5Me5)2Th­[N­(p-tolyl)­NNN­(p-tolyl)] (16), reaction of 1 with Me3SiCHN2 forms the bimetallic complex [(η5-C5Me5)2Th]2(μ-NNNCSiMe3)2 (17) concomitant with the elimination of mesitylene. The new complexes 2–15 and 17 were characterized by various spectroscopic techniques, including single-crystal X-ray diffraction studies.