Dilithium ethynylbis

Athene synthesis. A new synthesis of alkenes involves treatment of dilithium ethynylbis(trialkylborates) (1) with cyanogen bromide and a base (sodium methoxide). If cyanogen bromide and sodium methoxide are used in equimolecu-lar amounts, franr-alkenes (2) are formed mainly. When 3 eq. of cyanogen bromide and 1 eq. of base are used, tri- and tetrasubstituted alkenes, (3) and (4), are formed. 

Dilithium ethynylbis(lrialkylborates), 148 Dilithium tris(pent-l-ynyl)cuprate, 203 Dimedone, 611 Dimerization, 145... 

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