Synthetic and structural study of the coordination chemistry of a peri-backbone-supported phosphino-phosphonium salt

Synthesis of a 1-aza-2-phospha-acenaphthene complex profiting from coordination enabled chloromethane elimination

Despite debate on intramolecular N→P interactions in peri-substituted naphthalene derivatives their coordination chemistry has not yet been reported. Herein, we describe bonding in and reactivity of dichloro(8-dimethylamino-1-naphthyl)phosphane towards pentacarbonyltungsten(0) reagents. A 1-aza-2-phospha-acenaphthene complex was obtained via the unexpected elimination of chloromethane enabled through P-coordination. Theoretical DFT calculations provide insights into P⋯N pnictogen bonding interaction as well as the reaction pathway of the elimination reaction.

Reversible P-P bond cleavage at an iridium(III) metal centre

Treatment of a κ¹-P-monodentate bicyclic diphosphane iridium(III) complex with a labile gold(I) precursor afforded an unusual Ir^III/Au^I complex in which the P-P single bond has been cleaved. This reaction was cleanly reversed upon addition of tertiary phosphine. Carbon-carbon bond activation, across neighbouring P₂C₂N rings of the coordinated bicyclic diphosphane, occurred upon thermolysis of the Ir^III/Au^I complex.

Modulating the reactivity of phosphanylidenephosphoranes towards water with Lewis acids

Phosphanylidenephosphoranes of the type R−P(PR’3), also known as phospha-Wittig reagents, can be utilized in a variety of bond activation reactions exploiting their phosphinidenoid reactivity. In here, we thoroughly show that...

Spontaneous dehydrocoupling in peri-substituted phosphine-borane adducts

Bis(borane) adducts Acenap(PiPr2·BH3)(PRH·BH3) (Acenap = acenaphthene-5,6-diyl; 4a, R = Ph; 4b, R = ferrocenyl, Fc; 4c, R = H) were synthesised by the reaction of excess H3B·SMe2 with either phosphino-phosphonium salts [Acenap(PiPr2)(PR)](+)Cl(-) (1a, R = Ph; 1b, R = Fc), or bis(phosphine) Acenap(PiPr2)(PH2) (3). Bis(borane) adducts 4a-c were found to undergo dihydrogen elimination at room temperature, this spontaneous catalyst-free phosphine-borane dehydrocoupling yields BH2 bridged species Acenap(PiPr2)(μ-BH2)(PR·BH3) (5a, R = Ph; 5b, R = Fc; 5c, R = H). Thermolysis of 5c results in loss of the terminal borane moiety to afford Acenap(PiPr2)(μ-BH2)(PH) (14). Single crystal X-ray structures of 3, 4b and 5a-c are reported.