Radical addition to oxime ethers for asymmetric synthesis of beta-amino acid derivatives.

The diastereoselective alkyl radical addition to chiral oxime ethers was studied with a view to preparing enantiomerically pure alpha,beta-dialkyl-beta-amino acid derivatives. The phase transfer-catalyzed alkylation of Oppolzer's camphorsultam derivative of oxime ether proceeded smoothly to give the alkylated N-(beta-oximino)acyl derivatives. In the presence of BF3.OEt2, radical addition to the oxime ethers proceeded using triethylborane as the radical initiator to give alpha,beta-dialkyl-beta-amino acid derivatives with excellent diastereoselectivity.

[1]  Mei Fang Liu,et al.  Recent advances in the stereoselective synthesis of β-amino acids , 2002 .

[2]  G. Friestad,et al.  Intermolecular alkyl radical addition to chiral N-acylhydrazones mediated by manganese carbonyl. , 2001, Journal of the American Chemical Society.

[3]  F. Fülöp,et al.  The chemistry of 2-aminocycloalkanecarboxylic acids. , 2001, Chemical reviews.

[4]  G. Friestad.  Addition of carbon-centered radicals to imines and related compounds , 2001 .

[5]  J. Qin,et al.  Highly Stereoselective Intermolecular Radical Addition to Aldehyde Hydrazones from a Chiral 3-Amino-2-oxazolidinone , 2000 .

[6]  Ueda,et al.  Free-radical reaction of imine derivatives in water , 2000, The Journal of organic chemistry.

[7]  H. Miyabe,et al.  Asymmetric Synthesis of α-Amino Acids Based on Carbon Radical Addition to Glyoxylic Oxime Ether , 2000 .

[8]  I. Ryu,et al.  New Radical Cascade Reactions Incorporating Multiple One-Carbon Radical Synthons: A Versatile Synthetic Methodology for Vicinal Singly and Doubly Acylated Oxime Ethers , 1999 .

[9]  M. Bertrand,et al.  Diethylzinc: A Chain-Transfer Agent in Intermolecular Radical Additions. A Parallel with Triethylborane , 1999 .

[10]  T. Naito,et al.  HETEROATOM RADICAL ADDITION-CYCLIZATION AND ITS SYNTHETIC APPLICATION , 1999 .

[11]  P. Renaud,et al.  Use of Lewis Acids in Free Radical Reactions. , 1998, Angewandte Chemie.

[12]  H. Miyabe,et al.  Intermolecular alkyl radical addition to the carbon-nitrogen double bond of oxime ethers and hydrazones , 1998 .

[13]  B. Giese,et al.  Synthesis of Trehazolin from D-Glucose. , 1998, The Journal of organic chemistry.

[14]  D. Curran,et al.  RADICAL CYCLIZATIONS OF ACYLGERMANE OXIME ETHERS AND HYDRAZONES : DIRECT ROUTES TO CYCLIC HYDRAZONES AND OXIMES , 1998 .

[15]  H. Miyabe,et al.  Carboncarbon bond formation via intermolecular carbon radical addition to aldoxime ethers , 1998 .

[16]  A. G. Fallis,et al.  Free radical cyclizations involving nitrogen , 1997 .

[17]  Sunggak Kim,et al.  Free Radical-Mediated Ketone Synthesis from Alkyl Iodides via Sequential Radical Acylation Approach , 1997 .

[18]  J. Marco-Contelles,et al.  TRIBUTYLTIN HYDRIDE-MEDIATED FREE-RADICAL CYCLIZATION OF ALLENE-TETHERED OXIME ETHERS AND HYDRAZONES , 1997 .

[19]  Travis T Wager,et al.  TOTAL SYNTHESIS OF ENT-LYCORICIDINE VIA A THIYL RADICAL ADDITION-CYCLIZATION SEQUENCE , 1996 .

[20]  E. Swayze,et al.  Synthesis of Novel Nucleic Acid Mimics via the Stereoselective Intermolecular Radical Coupling of 3'-Iodo Nucleosides and Formaldoximes(1). , 1996, The Journal of organic chemistry.

[21]  S. Nencetti,et al.  Synthesis and Aldose Reductase Inhibitory Activity of Some N-(Aroyl)-N- (arylalkyloxy)-glycines and -β-Alanines. , 1996 .

[22]  Juyoung Yoon,et al.  NOVEL RADICAL REACTION OF PHENYLSULFONYL OXIME ETHERS. A FREE RADICAL ACYLATION APPROACH , 1996 .

[23]  I. Ryu,et al.  Tandem Radical Reactions of Carbon Monoxide, Isonitriles, and Other Reagent Equivalents of the Geminal Radical Acceptor/Radical Precursor Synthon. , 1996, Chemical reviews.

[24]  J. Marco-Contelles,et al.  Intramolecular reductive coupling of carbonyl-tethered oxime ethers promoted by samarium diiodide: A powerful method for the stereoselective synthesis of aminocyclopentitols , 1995 .

[25]  J. Kilburn,et al.  Synthesis of spirocycles by radical cyclisations of methylenecyclopropane derivatives , 1995 .

[26]  T. Naito,et al.  A novel and concise synthesis of aminocyclopentitols and 1-deoxynojirimycin via radical cyclization of oxime ethers , 1995 .

[27]  G. Hollingworth,et al.  Cascade Radical Cyclization-Fragmentation-Transannular-Ring Expansion Reactions Involving Oximes. A New Approach to Synthesis of Angular Triquinanes , 1995 .

[28]  H. Miyabe,et al.  Total Synthesis of (-)-Balanol , 1994 .

[29]  W. Oppolzer,et al.  Asymmetric Synthesis of α‐Amino Acids and α‐N‐Hydroxyamino Acids from N‐Acylbornane‐10,2‐sultams: 1‐chloro‐1‐nitrosocyclohexane as a practical [NH] equivalent , 1992 .

[30]  T. Hanamoto,et al.  Sml2-promoted ketyl radical addition to O-benzyl formaldoxime. A new aminomethylation , 1991 .

[31]  W. Oppolzer.  Camphor as a natural source of chirality in asymmetric synthesis , 1990 .

[32]  D. Hart,et al.  Bis(trimethylstannyl)benzopinacolate-mediated intermolecular free-radical carbon-carbon bond-forming reactions: a new one-carbon homologation , 1988 .

[33]  W. Oppolzer.  Metal-directed stereoselective functionalization of alkenes in organic synthesis , 1988 .

[34]  W. Oppolzer.  Camphor derivatives as chiral auxiliaries in asymmetric synthesis , 1987 .