Amination, Aminocarbonylation, and Alkoxycarbonylation of Allenic/Propargylic Pd Intermediates Derived from Nonracemic Propargylic Mesylates: Synthesis of Nonracemic Propargyl Amines, Allenic Amides, and Butenolides
Structure Investigations of (ent)-Cladospolide D by De Novo Synthesis and Kinetic and Thermodynamic Isomerization
作者:John Penn、George O’Doherty、Yalan Xing
DOI:10.1055/s-0029-1217606
日期:2009.9
dihydroxylation of a dienoate installed the remaining stereochemistry. The de novo asymmetric route allowed for the asymmetric synthesis of three members of the cladospolide natural products and correctly established the structure for cladospolide D. cladospolides B-D - asymmetric synthesis - natural product synthesis - E/Z-alkene isomerization
De Novo Asymmetric Synthesis of Cladospolide B−D: Structural Reassignment of Cladospolide D via the Synthesis of its Enantiomer
作者:Yalan Xing、George A. O’Doherty
DOI:10.1021/ol9000119
日期:2009.3.5
The enantioselectivesynthesis of cladospolide B, C, and (ent)-cladospolide D has been achieved in 11−15 steps from 1-nonyne. The route relies upon an alkyne zipper reaction to relay an ynone and dienoate functional groups across a nine carbon fragment, which enables a highly enantioselective Noyori ynone reduction and a diastereo- and regioselective Sharpless dihydroxylation of a dienoate. In addition
[2,3] Wittig rearrangement of nonracemic propargyl ethers leading to allenes of high stereochemical integrity
作者:James A. Marshall、Edward D. Robinson、Antonio Zapata
DOI:10.1021/jo00286a013
日期:1989.12
Synthesis of enantioenriched homopropargylic alcohols through diastereoselective SE' additions of chiral allenylstannanes to aldehydes
作者:James A. Marshall、Xiao Jun Wang
DOI:10.1021/jo00030a036
日期:1992.2
Allenylstannanes (S)-4 and (R)-4, available in ca. 90% ee from alkynones 1 through reduction with the LiAlH4-Darvon alcohol or -ent-Darvon alcohol complex, followed by S(N)2' displacement on the derived mesylates (R)-3 or (S)-3 with Bu3SnLi.CuBr.Me2S, readily add to various aldehydes under Lewis acid catalysis to afford optically active homopropargylic alcohols with good to excellent syn diastereoselectivity. With 2-(benzyloxy)propanal (48), MgBr2-catalyzed reactions are highly stereoselective, affording the syn adduct 49 from the (S)-stannane (S)-4 and the anti adduct 52 from the (R)-stannane (R)-4. BF3-promoted additions give mainly or exclusively the syn adducts 49 and 51. Additions of (S)- and (R)-4 to (R)-3-(benzyloxy)-2-methylpropanal (61) yield the syn adducts 62 and 64 as major or exclusive products.
MARSHALL, JAMES A.;ROBINSON, EDWARD D.;ZAPATA, ANTONIO, J. ORG. CHEM., 54,(1989) N5, C. 5854-5855
作者:MARSHALL, JAMES A.、ROBINSON, EDWARD D.、ZAPATA, ANTONIO