Carben- und Carbin-Komplexe des Technetiums und Rheniums - Synthese, Struktur und Reaktionen / Carbene and Carbyne Complexes of Technetium and Rhenium - Synthesis, Structure and Reactions

[Tc(NO)Cl(Cp)(PPh3)] – A Technetium(I) Compound with an Unexpected Synthetic Potential

“…The nitrosyl ligand is linearly bonded and, thus, must be regarded as a formal NO + as in the other complexes of this study. The Tc−C(11) carbene bond of 2.013(4) Å is only slightly longer than the value in [Tc(Cp*)(CO) 2 {C(Ph)OEt}] (1.97(2) Å), [48] but clearly longer than in the vinylidene complex [Tc(dppe) 2 Cl{=C=C(H)Ph}] (1.861(9) Å) [55] . The C6−C7 and C7−C8 bonds are in the normal range of single bonds, which excludes the formation of an alkenylphosphonio moiety as in the ruthenium compounds of ref.…”

“…The only other one, [Tc(Cp*)(CO) 2 {C(Ph)OEt}], has been prepared by Fischer et al . following the classical route by the subsequent treatment of a [Tc(Cp*)(CO) 3 ] with LiPh and (Et 3 O)(BF 4 ) [48] . In addition to the metal‐driven formation of a carbene from an alkyne and an alcohol, the isolated product 5 a shows another remarkable feature: the addition of PPh 3 and the formation of an alkylphosphonio substituent, which finally leads to a doubly charged organometallic cation.…”

Rhenium and technetium complexes with N-heterocyclic carbenes – A review

“…They were prepared by the addition of LiCH 3 or LiC 6 H 5 to [Tc 2 (CO) 10 ] or [Re 2 (CO) 10 ] and subsequent methylation. The products have the general formula [(CO) 9 M 2 C(OCH 3 )R] (1) (M = Re, Tc; R = CH 3 , C 6 H 5 ) [5], and this synthetic route has successfully been applied for further examples containing additional {Cp*} À (2) or PPh 3 ligands (3) [6,7].…”

“…The insertion of the organic isothiocyanate EtO 2 CN@C@S into the rhenium-rhenium single bond of [Re 2 (CO) 9 (MeCN)] and subsequent rearrangement results in the formation of two dimeric compounds (6), which each contain one (EtO 2 C) 2 NC@NCS 2 ligand [13,14]. The central unit of this moiety can formally be regarded as a heteroatom-stabilised carbene functionality.…”

Isolation of the key intermediates of base-promoted borylene–carbonyl coupling reactions

“…This initially somewhat peculiar reactivity became more understandable when it was compared with the well-studied ligand-induced C-C coupling reactions of carbyne complexes. [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Borylene complexes are isoelectronic to carbyne complexes, and borylene ligands are isolobal to carbonyl ligands. Therefore, despite the drastically different chemical properties of boron compared to those of its neighbor element carbon, there is a close resemblance between borylene and carbyne transition metal systems (Chart 2).…”