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η³ -Coordination and Functionalization of the 2-Phosphaethynthiolate Anion at Lanthanum(III)*.

ABSTRACT: We present the η³ -coordination of the 2-phosphaethynthiolate anion in the complex (PN)₂ La(SCP) (2) [PN=N-(2-(diisopropylphosphanyl)-4-methylphenyl)-2,4,6-trimethylanilide)]. Structural comparison with dinuclear thiocyanate-bridged (PN)₂ La(μ-1,3-SCN)₂ La(PN)₂ (3) and azide-bridged (PN)₂ La(μ-1,3-N₃ )₂ La(PN)₂ (4) complexes indicates that the [SCP]^- coordination mode is mainly governed by electronic, rather than steric factors. Quantum mechanical investigations reveal large contributions of the antibonding π*-orbital of the [SCP]^- ligand to the LUMO of complex 2, rendering it the ideal precursor for the first functionalization of the [SCP]^- anion. Complex 2 was therefore reacted with CAACs which induced a selective rearrangement of the [SCP]^- ligand to form the first CAAC stabilized group 15-group 16 fulminate-type complexes (PN)₂ La{SPC(^R CAAC)} (5 a,b, R=Ad, Me). A detailed reaction mechanism for the SCP-to-SPC isomerization is proposed based on DFT calculations.

SUBMITTER: Watt FA

PROVIDER: S-EPMC8252525 | biostudies-literature |

REPOSITORIES: biostudies-literature

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