Reactivity of an Aryl-Substituted Silicon−Silicon Triple Bond: Reactions of a 1,2-Diaryldisilyne with Alkenes

Abstract

The reactivity of a bulky, diaryl-substituted disilyne, Ar-Si identical withSi-Ar, was examined for the first time. Reaction of the disilyne with ethylene yielded an ethylene-bridged bis(silacyclopropane), which is interpreted as a further reaction product of the initially formed 1,2-disilacyclobutene species with ethylene. A cyclohexane fused with a 1,2-disilacyclobutene was obtained in the reaction with cyclohexene. In the reaction with 2,3-dimethyl-1,3-butadiene, a tricyclo derivative was isolated from the complex product mixture.

A New Family of Multiple-Bond Compounds between Heavier Group 14 Elements

“…For example, the reaction of 32 with ethylene would be initiated by the nucleophilic attack of H 2 C=CH 2 toward the slipped ³* orbital on one of the silicon atoms in 32 to give silylsilylene 42 followed by ring-expansion to give the corresponding disilacyclobutene 43. 39 This type of reactivity of a disilyne, a formal [2 + 2] cycloaddition, has been demonstrated in previous reports on the reaction of disilynes 34a and 34b with ethylene or 2-butene, 31,41 and also in our Bull. Chem.…”

“…Thus, we have examined the reactions of 1,2-diaryldisilyne 32 with ethylene, cyclohexene, 2,3-dimethyl-1,3-butadiene, and acetylene (Scheme 12), resulting in a diversity of reactivities of 32 toward such CC multiple bond systems. 39,40 Taking into consideration a reasonable reaction mechanism, all of these reactions would be triggered by the attack of CC ³-bond toward the slipped ³* orbital of the Si¸Si triple bond. For example, the reaction of 32 with ethylene would be initiated by the nucleophilic attack of H 2 C=CH 2 toward the slipped ³* orbital on one of the silicon atoms in 32 to give silylsilylene 42 followed by ring-expansion to give the corresponding disilacyclobutene 43.…”

“…9 (2013)observations of the reaction of 32 with cyclohexene giving 39 (Scheme 13). 39 Further reaction of cyclic disilene 43 with ethylene would then occur to give silylene 44, which would be trapped by a third molecule of ethylene via [1 + 2] cycloaddition to give the final product of 38 (Scheme 14). Furthermore, reaction of 32 with acetylenes giving disilabenzene derivatives 41 40 should be attributed to the same reactivity of silyldisilyne 34b with phenylacetylene 41 shown in the previous report, where the trigger of the reactions would be again the nucleophilic attack of acetylene toward the silicon center followed by the rearrangement to give the corresponding disilacyclobutadiene derivatives.…”

Intramolecularly Coordinated Tin(II) Selenide and Triseleneoxostannonic Acid Anhydride

“…[21] All these experiments afforded insights into the nature of the E E triple bonds. Scission of the Si Si or Ge Ge triple bond was observed by the addition of an olefin [3,9,[22][23][24][25][26][27] and most recently, Power and coworkers nicely outlined the cleavage of the SnSn multiple bond in the distannyne [ArSnSnAr] (Ar = C 6 H 3 -2,6-(C 6 H 3 -2,6-iPr 2 ) 2 ) by complexation with two molecules of either ethylene or norbornadiene or by cyclic polyolefinic molecules. [28,29] Moreover, the latest study dealing with the reactivity of [ArSnSnAr] with cyclooctatetraene (cot) showed the powerful reducing character of the tin(I) compound towards neutral cot.…”

Activation of Small Molecules by Compounds that Contain Triple Bonds Between Heavier Group‐14 Elements

“…BbtSi SiBbt 7 reacts with an excess amount of ethylene to afford the unexpected product 37 (Type II), [42] which contains two silacyclopropane moieties and three molecules of ethylene (Scheme 19), and exhibits remarkable thermal stability (Scheme 19). BbtSi SiBbt 7 reacts with an excess amount of ethylene to afford the unexpected product 37 (Type II), [42] which contains two silacyclopropane moieties and three molecules of ethylene (Scheme 19), and exhibits remarkable thermal stability (Scheme 19).…”