2007

Ring closure reactionsO 0130 Metal-Catalyzed Regioselective Oxy-Functionalization of Internal Alkynes: An

Entry into Ketones, Acetals, and Spiroketals. — A new and efficient method for the Pt(II) and Au(I)-catalyzed oxy-functionalization of unactivated internal alkynes is re-ported. [PtCl2(C2H4)]2 is used as selective catalyst for the intramolecular hydroalkoxy-lation of 5-alkynols and 3-alkynols as well as for tandem hydroalkoxylation/acetal for-mation. A new catalyst system consisting of MeAuPPh3 and AgPF6 is used for the 5-exo cycloisomerization of 4-alkynols. — (LIU, B.; DE BRABANDER*, J. K.; Org. Lett. 8 (2006) 21, 4907-4910; Dep. Biochem., Univ. Tex. Southwest. Med. Cent., Dallas, TX 75390, USA; Eng.) — S. Adam

10- 036

2007