Efficient Synthesis of Enantiopure Tretrahydroisoquinolines by Diastereoselective Intramolecular Heck Reaction Using α-Amino Acid Derivatives

Intramolecular Hydroaminations Mediated by Reductive Mercuration or n‐Butyllithium To Afford 3‐Methyl‐ and 3,4‐Dimethyl‐1,2,3,4‐tetrahydroisoquinolines

“…[25a–c] Pedrosa, Andrés and co‐workers argue that a coupling constant of zero Hertz between the hydrogens 3‐H and 4‐H is indicative of a trans 3,4‐disubstituted THIQ as a dihedral angle of 90 o is only possible for a trans relationship 25a. Perusal of the NMR spectroscopic data for a number of trans ‐3,4‐disubstituted THIQs described in the literature confirmed that coupling constant for the interaction between the 3‐H and 4‐H protons was invariably zero Hertz25b,25c or very close to it (for example 0.6 Hz) 21a. Unfortunately we were unable to find well characterized examples of 3,4‐disubstituted THIQs bearing substituents in a cis relationship.…”

Organolithium or Heck type cyclization of N-ortho-iodobenzyl-2-alkenylpyrrolidines to give indolizidines

“…There is precedent for carrying out such chemistry using an intramolecular Heck reaction with 6, R = Me. 8 We decided to explore this reaction for a selection of R groups using either Heck or intramolecular carbolithiation chemistry.…”

A Facile Synthesis of N-Boc-Protected Pyrroles by Cyclodehydration of γ-Amino-α,β-enals and -enones

“…General Procedure for the Wittig Homologation: N-(Boc)-α-aminoaldehydes 3aϪd were prepared from commercially available N-(Boc)amino alcohols by known procedures [24,26] and used directly in the Wittig homologation step without purification. The ylide [1.0 equiv.…”