Tetraethynylethene (1, TEE, Scheme 1) was introduced in 1991 as a useful building block for the synthesis of one-and two-dimensional p-conjugated scaffolds, such as poly(triacetylene) oligomers, expanded radialenes, and dehydroannulenes. [1] Incorporation of donor and acceptor substituents resulted in interesting electronic [1e, 2] and nonlinear optical properties. [1e, 3] Furthermore, the strain-free planarity allows reversible, photochemical cis±trans isomerization of cis-and trans-arylated TEEs without competition from undesirable thermal isomerization. [4] Cyanoethynylethenes (2±6, CEEs) are an interesting class of hybrid derivatives combining the scaffolding power of TEE with the electronic properties of tetracyanoethene (7, TCNE), which is one of the strongest organic electron acceptors known, and has been widely used in the formation of chargetransfer complexes. [5] So far, only derivatives of 3, with SiMe 3 (8 b, Scheme 2) or phenyl substituents, [6] and arylated derivatives of 6 [7] have been reported. Hopf and Kreutzer demonstrated that there was an enhanced reactivity of the triple bonds in derivatives of 3 and 6 towards Diels±Alder reactions [6] and in the [2þ2] cycloaddition to tetrathiafulvalene, with subsequent ring opening. [8] A similar reaction was also observed by Hirsch and co-workers at the terminal acetylene moiety of a,w-dicyanopolyynes. [9] We have now extended the family of CEEs and report herein the synthesis of 9±11 a (Scheme 2), silylated derivatives ZUSCHRIFTEN 3170