1. Synthesis of Heterocyclic Rings 1 (Introduction & Substitution)

2. Ring Synthesis Cyclization Reactions Cycloaddition Reactions Ring transformation

3. Baldwin's rules for ring closures Baldwin's rules in organic chemistry are a series of guidelines outlining the relative favourabilities of ring closure reactions in alicyclic compounds. They were first proposed by Jack Baldwin in 1976.organic chemistryalicyclicJack Baldwin

5. The rules classify ring closures in three ways: the number of atoms in the newly formed ring into exo and endo ring closures, depending whether the bond broken during the ring closure is inside (endo) or outside (exo) the ring that is being formed into tet, trig and dig geometry of the atom being attacked, depending on whether this electrophilic carbon is tetrahedral (sp 3 hybridised), trigonal (sp 2 hybridised) or digonal (sp hybridised).electrophilicsp 3 hybridisedsp 2 hybridisedsp hybridised

8. Cyclization Reactions Displacement at saturated carbons

10. Examples

11. The Darzens reaction (also known as the Darzens condensation or glycidic ester condensation) is the chemical reaction of a ketone or aldehyde with an α-haloester in the presence of base to form an α,β-epoxy ester,chemical reactionketonealdehydehaloesterbaseepoxyester This reaction was discovered by the organic chemist Auguste George Darzens in 1904. [3]Auguste George Darzens [3]

13. Feist-Benary Furane Synthesis