Reactions of (Ph)tBuP-P(SiMe3)Li·3THF with [(PNP)TiCl2] and [MeNacNacTiCl2·THF]: synthesis of first PNP titanium(iv) complex with the phosphanylphosphinidene ligand [(PNP)Ti(Cl){η2-P-P(Ph)tBu}]

We present the reactivity of [(PNP)TiCl2] and [MeNacNacTiCl2·THF] towards the lithium derivative of diphosphane (Ph)tBuP-P(SiMe3)Li·nTHF.

(2R,3S,4R)-3,4-Isopropylidenedioxy-2-(phenylsulfonylmethyl)pyrrolidin-1-ol

The title compound, C14H19NO5S, was prepared by nucleophilic addition of the lithium derivative of methylphenylsulfone to (3S,4R)-3,4-isopropylidenedioxypyrroline 1-oxide. There are four molecules in the asymmetric unit. The crystal structure determination confirms the configuration of the chiral centres as 2R,3S,4R. In the crystal, pairs of O—H...N hydrogen bonds link the molecules into dimers.

SiF-NH-Funktionelle Cyclodisilazane – Synthese und Reaktivität / SiF-NH-Functional Cyclodisilazane – Synthesis and Reactivity

Dichlorosilanes with bulky substituents R(Me3C)SiCl2 react with liquid ammonia to give geminal silyldiamines [R(Me3C)Si(NH2)2, 1: R = CH2 Me, 2: R = CHMe2]. In the reaction of the monolithium derivatives of these compounds with halosilanes 1-amino-1.3-disilazanes are obtained [(NH2)(Me3C)RSi-NH-SiR1R2R3; 3: R = CMe3, R1 = R2 = R3 = Me; 4: R = R1 = CMe3, R2 = R3 = Me; 5: R = R1 = R2 = CMe3, R3 = H; 6: R = R1 = CMe3, R2 = Me, R3 = F; 7: R = CHMe2, R1 = R2 = R3 = Me]. If monolithiated diamines are treated with trifluorosilanes cyclisation occurs to give (NH-Si(CMe3)2-NH-SiFR)cyclodisilazanes [R = N(SiMe3)(CMe3) (8); R = N(SiMe2CMe3)2 (9)]. 50% of the educts are recovered. The spirocyclic compound 10 is isolated from the reaction of the dilithiated 1-amino-1.3-disilazane 3 with F3SiN(SiMe2CMe3)2. NH-SiF-Functional cyclodisilazanes can be obtained in the reaction of the dilithium derivative of compound 4 with trifluorosilanes [(N(SiMe2CMe3)-Si(CMe3)2-NH-SiFR), R = Ph (11); R = CMe3 (12)]. The lithium derivative of 12 crystallises with TMEDA as adduct 13. In the reaction of the lithiated compound 12 with Me3SiCl, LiCl elimination and substitution of the N-atom is observed (14). The treatment of 13 with PhCHO leads to a 1.3-diaza-5-oxa-2.4-disila-cyclohexane (15 a, b). Starting from lithiated 12 the methoxysubstituted cyclodisiloxane 16 is accessible in the reaction with MeOH. As result of its reactivity towards Me2SiF2 the fluorosilyl-substituted cyclodisilazane 17 is obtained. Crystal structures of 9-11 and 13 have been determined.