atom. CCR of axially chiral alkenyl sulfoximines with Ni(PPh3)2Cl2 as a precatalyst and ZnPh2 does not require salt promotion and is stereoretentive. The reaction with Zn(CH2SiMe3)2, however, demands salt promotion and is not stereoretentive. CCR of axially chiralα‐methylated alkenyl sulfoximines afforded persubstituted axially chiralalkenes with high selectivity. Alkenyl (N‐triflyl)sulfoximines
Sulfoximine-directed osmylation: synthesis of enantiomerically pure dihydroxycycloalkanones
作者:Carl R. Johnson、Michael R. Barbachyn
DOI:10.1021/ja00320a053
日期:1984.4
On prepare une serie de dihydroxy-2,3 cyclohexanones et cyclo pentanones di- ou trisubstituees, a partir des cyclenones correspondantes par reaction avec le N-methyl S-methylS-phenyl sulfoximide
关于制备 une serie de dihydroxy-2,3 cyclohexones et cyclopentanones di-ou trisubstituees, a partir des cyclenones相应的反应 avec le N-methyl S-methyl S-phenyl sulfoximide
Total synthesis of the cytotoxic macrocycle (+)-hitachimycin
作者:Amos B. Smith、Thomas A. Rano、Noritaka Chida、Gary A. Sulikowski、John L. Wood
DOI:10.1021/ja00047a008
日期:1992.10
The first totalsynthesis of the antitumor antibiotic (+)-hitachimycin (a.k.a. stubomycin) (1) has been achieved in 22 steps and 1.1% overall yield. The cornerstone of the synthetic strategy was a highly stereoselective three-component coupling of (-)-5-methoxycyclopentenone (4) with a zincate derived from vinyl iodide 3a and aldehyde (-)-51
intermediate carrying a carbonyl group at C6. Asymmetric syntheses of the bicyclic C6-C14 ethynyl building blocks were carried out starting fromachiral bicyclic C6-C12 ketones by using the chiral lithium amide method. In the course of these syntheses, a new method for the introduction of an ethynyl group at the alpha-position of the carbonyl group of a ketone with formation of the corresponding homopropargylic
Diastereoselective additions of lithiated N-tertbutyldiphenylsilyl- S-methyl-S-phenylsulfoximine to imines and aldehydes
作者:Stephen G. Pyne、Branko Dikic
DOI:10.1016/s0040-4039(00)97851-1
日期:1990.1
Lithiated N-tert-butyldiphenylsilyl-S-methyl-S-phenylsulfoximine undergoes 1,2 addition to imines (R1CHNPh) and aldehydes (RCHO) to give diastereomeric adducts. The diastereoselection of the former reactions is dependent on the steric demand of the imine substituent R1, while that of the latter is independent of the steric demand of the aldehyde substituent R.