Vicinal Dilithioalkenes by Addition of Lithium to Simple Cyclic and Acyclic Alkynes

✍ Scribed by Prof. Dr. Adalbert Maercker; Dipl.-Chem. Thomas Graule; Ulrich Girreser

• Publisher: John Wiley and Sons
• Year: 1986
• Tongue: English
• Weight: 234 KB
• Volume: 25
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.198601671

✦ Synopsis

Restmann on the occasion of his 60th birthday Addition of lithium to diphenylacetylene affords, depending on the conditions, either the unstable cis-dilithiostilbenel'] or the dimeric 1,4-dilithio-l,2,3,4-tetraphenyl-1,3-b~tadiene. [~] Only the latter has found applications as a difunctional organolithium compound in synthetic chemistry.[41 We have now attempted to extend this reaction to dialkylacetylenes in order to develop, ultimately, an approach to the synthesis of aliphatic, vicinal dilithioalkenes, which have not yet been prepared. ['] In order to exclude the possibility of lithium hydride elimination, the most important competing reaction in the synthesis of polylithium organic compounds,[61 we initially selected di-tert-butylacetylene as a starting material-however, without success. No reaction was observed, even after heating the compound with lithium powder for eight hours in diethyl ether, tetrahydrofuran (THF), or cyclopentane.