Mild and facile preparations of 2-substituted or 2,3-disubstituted indole compounds were achieved by RhH(CO)(Ph(3)P)(3) (4-10 mol %)-catalyzed reaction of N-propargylanilines in hexafluoroisopropyl alcohol (HFIP). The formation of indoles was proven to be derived from an o-allenylaniline intermediate, which was generated by the Rh(I)-catalyzed amino-Claisen rearrangement of N-propargylanilines. The catalytic system is also available for the one-pot synthesis of indoles by reacting N-alkylaniline (1 equiv) with propargyl bromide (1.3 equiv) in the presence of K(2)CO(3) (3 equiv) in HFIP. The active catalyst was proven to be [Rh(CO)(Ph(3)P)(2)]OCH(CF(3))(2) generated in situ from RhH(CO)(Ph(3)P)(3) and HFIP. The structure of [Rh(CO)(Ph(3)P)(2)]OCH(CF(3))(2) was confirmed by single-crystal X-ray crystallographic analysis.

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Fused pyridine derivatives R 0450 Rh(I)-Catalyzed Intramolecular Hetero-[4 + 2] Cycloaddition of ω-Alkynyl-vinyl Oximes. -Under optimized conditions, the process affords readily bicyclic pyridine skeletons as valuable building blocks of natural products. -(SAITO, A.; HIRONAGA, M.; ODA, S.; HANZAWA*, Y.; Tetrahedron Lett. 48 (2007) 39, 6852-6855; Lab. Org. React. Chem., Showa Pharm. Univ., Machida, Tokyo 194, Japan; Eng.) -Mais 03-144

Indole derivatives R 0140Rhodium (I)-Catalyzed Synthesis of Indoles: Amino-Claisen Rearrangement of N-Propargylanilines. -Treatment of N-propargylanilines under conditions A) allows a mild, facile, and efficient access to indole derivatives via amino-Claisen rearrangement. Direct one-pot synthesis of indoles starting from anilines and propargyl bromides is also possible. -(SAITO*, A.; ODA, S.; FUKAYA, H.; HANZAWA, Y.; J. Org. Chem. 74 (2009) 4, 1517-1524; Lab. Org. React. Chem., Showa Pharm. Univ., Machida, Tokyo 194, Japan; Eng.) -Jannicke