Synthesis and reactivity of mixed alkynylalanes by direct triethylamine-catalyzed alumination of terminal alkynes.

[reaction: see text] Terminal alumination of alkynes by DIBALH or trimethylaluminum can be performed in a simple manner in the presence of a small amount of triethylamine. This new Lewis-base-catalyzed process delivers mixed alkynyldialkylalanes of great interest, without the need of an initial deprotonation step with lithium or sodium derivatives followed by a transmetalation.