The palladium-catalyzed allylic substitution of 3-alkoxy-2-propenyl acetates and carbonates with various carbonucleophiles occurs alpha to the alkoxy group.
An Ireland−Claisen Approach to β-Alkoxy α-Amino Acids
作者:James P. Tellam、Gabriele Kociok-Köhn、David R. Carbery
DOI:10.1021/ol802169j
日期:2008.11.20
A diastereoselective Ireland-Claisen approach to beta-alkoxy alpha-amino acid esters is reported. Amino acid esters of enol ethereal allylic alcohols undergo facile syn-selective [3,3]-sigmatropic rearrangement via silyl keteneacetals. Substrate synthesis, rearrangement development, stereoselectivity, and product elaboration are discussed.
Remote Stereocontrol in [3,3]-Sigmatropic Rearrangements: Application to the Total Synthesis of the Immunosuppressant Mycestericin G
作者:Nathan W. G. Fairhurst、Mary F. Mahon、Rachel H. Munday、David R. Carbery
DOI:10.1021/ol203300k
日期:2012.2.3
3]-sigmatropic rearrangement has been used to access biologically important β,β′-dihydroxy α-amino acids. The rearrangement reported is highly stereoselective and offers excellent levels of remotestereocontrol. This strategy has been used to synthesize the natural immunosuppressant mycestericin G and ent-mycestericin G, allowing for a revision of absolute configuration of this natural product.
Development of the Ireland−Claisen Rearrangement of Alkoxy- and Aryloxy-Substituted Allyl Glycinates
作者:James P. Tellam、David R. Carbery
DOI:10.1021/jo1017124
日期:2010.11.19
The Ireland−Claisenrearrangement of 3-alkoxy- and 3-aryloxy-substituted allyl glycinates is presented. This [3,3]-sigmatropic rearrangement route offers direct access to syn β-alkoxy and β-aryloxy α-amino acid systems. In particular, N,N-diboc glycine esters rearrange with excellent diastereoselectivities (dr > 25:1). The synthesis of substrates, rearrangement optimization, and a discussion of stereoselection
stereoselective one‐potsynthesis of functionalized complex tricyclic polyethers has been achieved using the combination of secondary amine and lanthanide catalysis. This one‐pot quadruple reaction/Hetero‐Diels–Alder sequence gave good yields (per step) as well as excellent diastereo‐ and enantioselectivities. Furthermore, the particular combination of lanthanide complexes with organocatalysis is one of the