Synthesis of chiral γ-lactams via Rh(II) catalyzed intramolecular C–H insertion: α-substituents and conformational effects
作者:David L. Flanigan、Cheol Hwan Yoon、Kyung Woon Jung
DOI:10.1016/j.tetlet.2004.10.159
日期:2005.1
γ-lactams are efficiently synthesized via Rh(II) catalyzed intramolecular C–H insertion from various α-diazoamides. Independent of α-substituents, regio- and stereoselectivities are enhanced through a conformational effect exerted by a bicyclictransitionstate.
Total Syntheses of (−)-α-Kainic Acid and (+)-α-Allokainic Acid via Stereoselective C−H Insertion and Efficient 3,4-Stereocontrol
作者:Young Chun Jung、Cheol Hwan Yoon、Edward Turos、Kyung Soo Yoo、Kyung Woon Jung
DOI:10.1021/jo701988j
日期:2007.12.1
Reported herein is a novel approach to the totalsyntheses of (−)-α-kainic acid and (+)-α-allokainic acid, where the stereochemistries on C(2), C(3), and C(4) of the pyrrolidine core were introduced efficiently and selectively. A regio- and stereoselective C−H insertion reaction was utilized to prepare the γ-lactam as an intermediate. A Michael-type cyclization of phenylsulfone with a conjugated acetylenic
A Novel Synthetic Route to Chiral γ-Lactams from α-Amino Acids via Rh-Catalyzed Intramolecular C−H Insertion
作者:Cheol Hwan Yoon、David L. Flanigan、Byong-Don Chong、Kyung Woon Jung
DOI:10.1021/jo0259717
日期:2002.9.1
biologically significant natural products. We herein described the synthesis of various chiral gamma-lactams viaintramolecular C-H insertion of alpha-diazo-alpha-(phenylsulfonyl)acetamides derived from alpha-amino acids, which possess various functional groups. The cyclizations were highly regio- and stereoselective to afford chiral gamma-lactam motifs in high yields.