Triple dehydrofluorination as a route to amidine-functionalized, aromatic phosphorus heterocycles

Abstract

An unexpected route to hitherto unknown amidine-functionalized phosphinines has been developed that is rapid and simple. Starting from primary amines and CF3-substituted λ3,σ2-phosphinines, a cascade of dehydrofluorination reactions leads selectively...

A π‐Extension Process from 9‐Phosphaanthracene Leading to Phosphatetraphenes and Phosphatetracenes

“…Figure 2a shows molecular structure of 12‐phosphatetraphene 1 in which the fused four rings construct an almost planar skeleton (see also Figure S3) and the meso‐ Mes aromatic ring is almost perpendicular to the phosphinine ring with dihedral angle of 84.10°. The geometric parameters around the phosphinine unit are comparable with those of isolated phosphinines [1f,4,6,15] and 9‐phosphaanthracene [5] . Two molecules of 1 face each other with the distance of 3.575 Å in the triclinic crystalline state (Figure 2b, Figure S4), but the unsymmetrical π‐conjugated system of 1 would be inconvenient for long range π‐π stackings.…”

“…The stabilization method revealed the structural aspects of 9-phosphaanthracenes including crystalline polymorphs and the fluorescence properties. [5,6] In the synthetic studies of peritrifluoromethylated 9-phosphaanthracenes, we utilized the spontaneous deamination reaction of diarylaminophosphine intermediates leading to 9-phosphaanthracenes (Figure 1b). This deaminative aromatization is promising for π-extending based on the 9-phosphaanthracene platform.…”

“…As a stabilizing method of the heavier anthracene congener, we previously established the peri‐ trifluoromethylation approach together with sterically demanding meso ‐aryl substituent. The stabilization method revealed the structural aspects of 9‐phosphaanthracenes including crystalline polymorphs and the fluorescence properties [5,6] . In the synthetic studies of peri ‐trifluoromethylated 9‐phosphaanthracenes, we utilized the spontaneous deamination reaction of diarylaminophosphine intermediates leading to 9‐phosphaanthracenes (Figure 1b).…”