Asymmetric Synthesis of (2<i>S</i>,6<i>S</i>)- and <i>meso</i>-(2<i>S</i>,6<i>R</i>)-Diaminopimelic Acids from Enantiopure Bis(sulfinimines)

Asymmetric Synthesis of (2S,6S)- and meso-(2S,6R)-Diaminopimelic Acids from Enantiopure Bis(sulfinimines

Concise Asymmetric Synthesis of α-Amino Acid Derivatives from <i>N</i>-Sulfinylimino Esters

Concise Asymmetric Synthesis of α-Amino Acid Derivatives from N-Sulfinylimino Ester

Asymmetric Synthesis of Substituted Homotropinones from <i>N</i>-Sulfinyl β-Amino Ketone Ketals. (−)-Euphococcinine and (−)-Adaline

Sulfinimine-derived N-sulfinyl β-amino ketone ketals on heating with NH4OAc:HOAc undergo a four-step intramolecular Mannich cyclization cascade reaction to give homotropinones, such as (−)-euphococcinine, in excellent yields as single isomers

Asymmetric Synthesis of <i>s</i><i>yn</i>-(2<i>R</i>,3<i>S</i>)<i>- </i>and <i>a</i><i>nti</i>-(<i>2S</i>,3<i>S</i>)-Ethyl Diamino-3-phenylpropanoates from <i>N</i>-(Benzylidene)-<i>p</i>-toluenesulfinamide and Glycine Enolates^†

Addition of differentially N-protected glycine enolates to enantiopure sulfinimines affords syn- and anti-α,β-diamino esters with high diastereoselectivities and good yields

Asymmetric Synthesis of Substituted Homotropinones from <i>N</i>-Sulfinyl β-Amino Ketone Ketals. (−)-Euphococcinine and (−)-Adaline

Sulfinimine-derived N-sulfinyl β-amino ketone ketals on heating with NH4OAc:HOAc undergo a four-step intramolecular Mannich cyclization cascade reaction to give homotropinones, such as (−)-euphococcinine, in excellent yields as single isomers

Asymmetric Synthesis of (−)-Nupharamine and (−)-(5<i>S</i>,8<i>R</i>,9<i>S</i>)-5-(3-Furyl)-8-methyloctahydroindolizidine from β-Amino Ketones and the Intramolecular Mannich Reaction

The asymmetric synthesis of the 2,3,6-trisubstituted piperidine core of the antitumor Nuphar alkaloids was readily achieved by using the intramolecular Mannich reaction and a sulfinimine-derived β-amino ketone

Asymmetric Synthesis of <i>syn</i>-α-Substituted β-Amino Ketones by Using Sulfinimines and Prochiral Weinreb Amide Enolates

syn-α-Substituted β-amino Weinreb amides are new chiral building blocks for asymmetric synthesis of syn-α-substituted β-amino acids, aldehydes, and ketones and are prepared by addition of prochiral lithium enolates of Weinreb amides to sulfinimines (N-sulfinyl imines)

Asymmetric Synthesis of the Carbocyclic Nucleoside Building Block (<i>R</i>)-(+)-4-Aminocyclopentenone Using δ-Amino β-Ketophosphonates and Ring-Closing Metathesis (RCM)

Amino keto-2,7-dienes undergo ring-closing metathesis (RCM) to give 4-aminocyclopentenones, valuable intermediates in the asymmetric construction of carbocyclic nucleosides. The key amino ketodienes were prepared using δ-amino β-ketophophonates, a new sulfinimine-derived chiral building block, and HWE chemistry

Asymmetric Synthesis of α-Substituted β-Amino Ketones from Sulfinimines (<i>N</i>-Sulfinyl Imines). Synthesis of the Indolizidine Alkaloid (−)-223A

Of the possible four stereoisomers, addition of the lithium enolate of 4-heptanone to sulfinimines resulted in only the syn- and anti-α-substituted β-amino ketones. The formation of the major syn-β-amino ketone was rationalized in terms of addition of the E-enolate to the C−N double bond of the sulfinimine via a six-member chelated chairlike transition state. The enolates of 4-heptanone were generated using LiHMDS in THF where a 1:2.5 E:Z enolate ratio was noted. In diethyl ether the E:Z ratio was 15:1 in favor of the E-enolate and explained in terms of Ireland's transition state model. Here increased steric interactions between the ethyl group and the carbonyl-LiN(TMS)2 moiety destabilize the transition state leading to the Z-enolate in the poorly coordinating diethyl ether solvent. This new synthesis of syn-α-substituted-β-amino ketones was applied to the concise enantioselective total synthesis of indolizidine (−)-223A, a 5,6,8-trisubstituted alkaloid isolated from the skin of the dendrobatide frog

Asymmetric Synthesis of Cyclic <i>cis</i>-β-Amino Acid Derivatives Using Sulfinimines and Prochiral Weinreb Amide Enolates

Cyclic cis-β-amino Weinreb amides, valuable building blocks for the asymmetric synthesis of cyclic β-amino acids derivatives, are readily prepared via ring-closing metathesis of sulfinimine-derived N-sulfinyl β-amino diene Weinreb amides. These unsaturated cyclic cis-β-amino Weinreb amides are valuable building blocks for the asymmetric synthesis of cyclic β-amino acid derivatives