Phosphinidene Reactivity of a Transient Vanadium P≡N Complex

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry
• Synthetic Inorganic Chemistry

Background:

• The preparation of coordination complexes involving heterodiatomic molecules like PN is challenging.
• Understanding the reactivity of low-valent phosphorus species is crucial for developing new synthetic methodologies.

Purpose of the Study:

• To report the use of anthracene chloride (ClPA) as a formal source of phosphorus(I).
• To investigate the formation of phosphorus-nitrogen compounds and explore the reactivity of transient phosphinidene intermediates.

Main Methods:

• Reaction of ClPA with Na[NV(N[tBu]Ar)3] to yield trimeric cyclo-triphosphane.
• Trapping experiments using peri-1,8-naphthalene disulfide (NapS2) to isolate intermediate species.
• Kinetic studies and [2+1]-cycloaddition reactions with radical clocks to elucidate reaction mechanisms.

Main Results:

• Synthesis of trimeric cyclo-triphosphane [PNV(N[tBu]Ar)3]3 (3) and dimeric [PNV(N[tBu]Ar)3]2 (2).
• Formation of phosphirene and phosphirane compounds (7 and 8) via trapping of transient phosphinidene.
• Evidence for singlet phosphinidene intermediate 1 and its reversible exchange reactions.

Conclusions:

• Anthracene chloride (ClPA) serves as an effective phosphorus(I) source for synthesizing PN compounds.
• Transient phosphinidene intermediates exhibit unique reactivity, enabling the formation of novel cyclic phosphorus-nitrogen structures.
• The observed reactivity expands the known chemistry of phosphinidenes beyond transition metal catalysis.