Crystal structure of (1′S,2′S,3S)-1′-benzoyl-2′-(4-methoxyphenyl)-1-methyl-2′,5′,6′,10b′-tetrahydro-1′H-spiro[indoline-3,3′-pyrrolo[2,1-a]isoquinolin]-2-one

In the title spiro compound, C34H30N2O3, the central pyrrolidine ring is fused with the tetrahydroisoquinoline ring, both having distorted envelope conformations, with the flap atoms being C and N, respectively. The methoxyphenyl group is attached to the pyrrolidine ring, and is disordered over two positions, with refined occupancies of 0.638 (6):0.362 (6) Å. The central pyrrolidine ring is inclined relative to the tetrahydroisoquinoline group, such that the dihedral between the non-flap atoms of each ring system is 11.29 (7)°. The spiro-linkage creates a dihedral angle of 83.26 (5)° between the indolinone ring and the non-flap atoms of the pyrrolidine ring. In the crystal, molecules are linked via C—H...O hydrogen bonds. For the major disorder component, these form C(11) chains that propagate parallel to the a axis.

White-light electroluminescence from a layer incorporating a single fully-organic spiro compound with phosphine oxide substituents

We have investigated the potential as an OLED emitter of a spiro compound with phosphine substituents initially designed as a host layer for triplet emitters.

[2+2+2] Annulation of N-(1-Naphthyl)acetamide with Two Alkynoates via Cleavage of Adjacent C–H and C–N Bonds Catalyzed by an Electron-Deficient Rhodium(III) Complex

It has been established that an electron-deficient cationic CpE-rhodium(III) complex catalyzes the non-oxidative [2+2+2] annulation of N-(1-naphthyl)acetamide with two alkynoates via cleavage of the adjacent C–H and C–N bonds to give densely substituted phenanthrenes under mild conditions (at 40 °C under air). In this reaction, a dearomatized spiro compound was isolated, which may support the formation of a cationic spiro rhodacycle intermediate in the catalytic cycle. The use of N-(1-naphthyl)acetamide in place of acetanilide switched the reaction pathway from the oxidative [2+2+2] annulation-lactamization via C–H/C–H cleavage to the non-oxidative [2+2+2] annulation via C–H/C–N cleavage. This chemoselectivity switch may arise from stabilization of the carbocation in the above cationic spiro rhodacycle by the neighboring phenyl and acetylamino groups, resulting in the nucleophilic C–C bond formation followed by β-nitrogen elimination.

A twist on Hellwinkel’s salt, [P(2,2′-biphenyl)2]+[P(2,2′-biphenyl)3]–

Treating PCl5 with C12H8Li2, generated from either C12H10, C12H8Br2, or C12H8I2, affords three products in different ratios depending on the source of the lithiated biphenyl. Hellwinkel’s salt [P(C12H8)2][P(C12H8)3] ([1][2]) and another product [P(C12H8)(C24H16)][P(C12H8)3] ([1′][2]) were obtained by reacting PCl5 with 2,2′-dilithiobiphenyl [Route A: 2.5 equiv.; obtained from biphenyl, n-BuLi, and TMEDA; Route B: 3.0 equiv.; obtained from 2,2′-diiodobiphenyl and n-BuLi; Route C: 4.0 equiv.; obtained from 2,2′-dibromobiphenyl and n-BuLi]. The synthesis, isolation, and characterization of the chiral spiro-compound [1′][2] and the characterization of the pentavalent phosphorane [P(C12H8)2(C12H9)] (3) are reported. The complex [1′][2] was characterized by 31P{1H} NMR spectroscopy, X-ray crystallography, and mass spectrometry. The pentavalent compound (3) was characterized by 31P{1H} NMR spectroscopy and X-ray crystallography.