Propargylidyne and Pentadiynylidyne Polyfunctionalised Polycyclic Aromatic Hydrocarbons

Abstract

The Pd0/AuI mediated [C1+C2] cross‐coupling reactions of [W(≡CBr)(CO)2(Tp*)] (Tp*=hydrotris(dimethylpyrazolyl)borate) and trimethylsilylethynyl‐substituted arenes afford new polycyclic aromatic hydrocarbon propargylidynes [W(≡CC≡CR)(CO)2(Tp*)] (R=9‐anthracenyl, 1‐pyrenyl). The strategy extends to the first bis(propargylidyne) and bis(pentadiynylidyne) complexes bridged by phenyl or anthracenyl spacers, and to a tetrakis(propargylidyne) connected through a pyrene core.

Synthesis and reactivity of 9,10-bis(4-trimethylsilylethynylbuta-1,3-diynyl)anthracene derived chromophores

“…The title compound 9,10-bis(trimethylsilylbuta-1,3-diyn-1-yl) anthracene (1) 1 was previously prepared on gram-scale by a strategy modified from Low's synthesis of the shorter 9,10-bis (2-trimethylsilylethynyl)anthracene, 7 resulting in yields of 49%. 7 Treatment of anthraquinone with LiCuCCuCSiMe 3 (itself prepared from 1,4-bis(trimethylsilyl)butadiyne and MeLi•LiBr) followed by aqueous workup gives syn-9,10-bis(trimethylsilylbuta-1,3-diyn-1-yl)-9,10-dihydroanthracene-9,10-diol.…”

“…Both species were isolated as brown solids in excellent yields, albeit with a trace amount of [AuCl(PR 3 )] contamination often found to be present (estimated <5% by 31 P{ 1…”

“…This has included systems that involve metal-carbon multiple bonding, as demonstrated by the one-pot desilylation and cross-coupling reactions that install this motif between two tungsten centres connected by WuC triple bonded termini. 1 During the course of this work it became apparent that compounds containing a 9,10-bis(butadiynyl)anthracene moiety are far scarcer and less studied than might be expected. This contrasts rather starkly with the shorter 9,10-bis(alkynyl) anthracene derivatives, shorter by just one CuC unit on each side, which have significant, wide-ranging uses due to their strong fluorescence and high quantum yields.…”

“…carbon analogues, although steric constraints can force the CvP bond out of conjugation. 6 Though scarcely studied, these preliminary results indicate that the 9,10-bis(butadiynyl)anthracene building block shows promise for electro-optical applications, the study of which should now benefit from the recent availability of 9,10-bis(trimethylsilylbuta-1,3-diyn-1-yl)anthracene (1). 1 Herein, we describe investigations into the organometallic chemistry of this useful reagent.…”

Organometallic Chemistry of Transition Metal Alkylidyne Complexes Centered at Metathesis Reactions

“…Group 5 metal complexes have been described for a few with a V(V) 13,14 or Ta(V) 15−17 center. The most common hydrocarbyl alkylidynes are those of group 6 metals, which have been isolated for a number of species with a M(IV) (M = Cr, Mo, W) 1a−e, 18,19 or a M(VI) (M = Mo, W) 20, 21 center, and for a few with a Mo(V) or W(V) center. 22 For group 7, rhenium is known to form a variety of hydrocarbyl alkylidynes with a Re(V), Re(VI), or Re(VII) center, 23 and a few Mn(V) 24 and Tc(V) 25 complexes are also known.…”