Directed Aldol Condensations: β‐Phenylcinnamaldehyde

Abstract

Directed aldol condensations: β‐phenylcinnamaldehyde reactant: 99.2 g. (1.00 mole) of freshly distilled cyclohexylamine reactant: 44.1 g. (1.00 mole) of freshly distilled acetaldehyde intermediate: N ‐ethylidenecyclohexylamine solvent: 2.53 g. (3.60 ml. or 0.0250 mole) of pure diisopropylamine intermediate: N ‐(3‐hydroxy‐3,3‐diphenylpropylidene)cyclohexylamine product: β‐phenylcinnamaldehyde

Synthesis of an Isophorone‐Based Nonlinear Optical Chromophore

“…N-Cyclohexyl-acetimine was prepared as previously described. [10] Melting points were determined on an electrothermal capillary melting point apparatus and are not corrected.…”

“…Silyl ether protection gave 5 for subsequent Wittig directed-aldol reaction [8,9] with the acetaldehyde equivalent, N-cyclohexyl-acetimine, [10] to give moderate yield of a mixture of Z and E aldehydes 6a,6b, respectively. The Z : E ratio was 33 : 67 by 1 H-nuclear magnetic resonance (NMR).…”

Acetate-Promoted Aldol-Type Reaction: Scope and Reactivity of Acetates and Aldehydes

“…1a To overcome such limit, several indirect methods such as employing silyl enol ether, 22 2-formylketone, 23 enamine, 24 lithiated imine, 25 and lithiated enamine, 26 have been designed, but sometimes long reaction sequence and expensive reagents are the bottle-necks for the general use.…”