lO.XIT.9 I ) Hydroboration of aliphatic 1-alkynes with freshly prepared dicyclohexylborane (1 mol-equiv., hexane), treatment of the resulting [(E)-1-alkenyl]boranes 5 with Et'Zn or Me,Zn (1.05 mol-equiv.) followed by addition of (-)-3-exo-(dimethylamino)isoborneol (DATB, 8; 0.01 mol-equiv.), subsequent addition of a solution of an aromatic or aliphatic aldehyde (1 mol-equiv., hexane). and quenching with aq. NH,CI provided (E)-ally1 alcohols 6 usually in 713-950/0 yield with 79-98% enantiomeric excess (Scheme 3 and Tuble).Optically pure secondmy ally1 alcohols 3b (as well as their antipodes) are key intermediates in organic synthesis. Recently, we have presented a new enantioselective approach to compounds of the type 3b based on 'asymmetrically catalyzed' additions of (l-alke-ny1)zinc reagents l a [l] and Ib [2] to aromatic and aliphatic aldehydes (Scheme I)').We now envisaged an analogous ligand-controlled 1 -alkenyl transfer from mixed (1-alkenyl)(alkyl)zinc reagents such as Ic focussing our attention on the following points: 1 ) good accessibility, 2) chemical and stereochemical stability'), 3 ) exclusive transfer of S( /lr,nlc I

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