Stereoselective Synthesis

A. ­ Introduction

i) Stereochemical words

ii) Stereospecificity & Stereoselectivity

B. ­ Reactions of Prochiral Substrates.

I. Stereospecific reactions of prochiral substrates (sp2 to sp3). Using defined double bond geometry to introduce stereochemistry

i) Cycloaddition reactions

ii) Hydrogenation

iii) Epoxidation & Dihydroxylation

II. Stereoselective reactions of prochiral substrates (sp2 to sp3)

i) Stereoselective aldol ­ Zimmerman-Traxler

III. Cyclic compounds

i) Addition of Nucleophiles to cyclic ketones.

ii) Exocyclic enolates

C. ­ Using One Chiral Centre to Control Another

I. Cyclic Compounds {axial vs. equatorial attack & microscopic reversibility}

i) Endocyclic enolates

ii) Opening epoxides

II. Cyclic Intermediates

i) Iodolactonisation

III. Acyclic Compounds with Cyclic Transition States

i) Epoxidation

ii) Chelation control

iii) Claisen rearrangement

iv) Stereoselective reduction of b-hydroxy ketones

v) Aldol revisited

IV. Acyclic compounds

i) Addition of Nucleophiles to acyclic ketones

{Bürgi-Dunitz, Felkin-Ahn & Electronic influences}

ii) Electrophilic reactions of Alkenes ­ Houk & Electronic effect of allylic substituent

iii) Allyl silanes

Time permitting ­

D. ­ Stereoselective & Stereospecific Reactions i) Cycloadditions ii) Tethers

E. ­ The Anomeric Effect

i) Dispiroketals

1. E. L. Eliel and S. H. Wilen, 'Stereochemistry of Organic Compounds', Wiley & Sons, 1994.

2. A. J. Kirby, 'Stereoelectronic Effects', Oxford University Press, 1996