Heteroatom-Conjugated Allenylidene and Related Cumulenylidene Ligands. In: Chauvin R, Canac Y, editors. Transition Metal Complexes of Neutral eta1-Carbon Ligands. Berlin: Springer Berlin Heidelberg; 2010. pp. 219-52. [DOI: 10.1007/978-3-642-04722-0_7]

Synthesis and reactivity of selenium functionalised allylidynes and propargylidynes

The reactions of the trimethylsilylpropargylidyne [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSiMe3)(CO)2(Tp*)] (1: Tp* = hydrotris(dimethylpyrazolyl)borate) towards selenium centred reagents when treated with tetrabutylammonium fluoride (TBAF) were explored in order to prepare alkynylselenolato propargylidynes, e.g., [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSePh)(CO)2(Tp*)]. Treating 1 with TBAF and PhSeSePh resulted in E and Z isomers of the vinylcarbyne (allylidyne) complex [W{[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]CHSePh}(CO)2(Tp*)] in addition to traces of the trisubstituted derivative [W{[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]C(SePh)2}(CO)2(Tp*)]. Reactions with PhSeCl resulted in the isolation of bimetallic bis-substituted allylidyne complex [(Tp*)(CO)2W[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]C(SePh)C[triple bond, length as m-dash]CC[triple bond, length as m-dash]W(CO)2(CO)2(Tp*)] as well as the desired selenolatopropargylidyne [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSePh)(CO)2(Tp*)].

Synthesis and reactivity of an anionic allenylidene complex

The reaction of [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSiMe₃)(CO)₂(Tp*)] (Tp* = hydrotris(dimethylpyrazolyl)borate) with MeLi generates the first example of an anionic allenylidene complex Li[W([double bond, length as m-dash]C[double bond, length as m-dash]C[double bond, length as m-dash]CMeSiMe₃)(CO)₂(Tp*)] which reacts with electrophiles (H⁺, Me⁺) at the β-carbon to afford vinylcarbyne (allylidyne) complexes [W([triple bond, length as m-dash]CCE[double bond, length as m-dash]CMeSiMe₃)(CO)₂(Tp*)] (E = H, Me), and with bromine provides the unprecedented binuclear bis(carbyne) complex {C([double bond, length as m-dash]CMeSiMe₃)C[triple bond, length as m-dash]W(CO)₂(Tp*)}₂via oxidative C-C coupling at the β-carbon.

Homoleptic gold(i) N-heterocyclic allenylidene complexes: excited-state properties and lyotropic chromonics

Phosphorescent Au(i) bis(N-heterocyclic allenylidene) complexes exhibit panchromatic transient absorption upon electronic photo-excitation and can self-organize into lyotropic chromonic mesophases in aqueous solutions.