844857-46-1

Upstream product

• 57486-69-8 methyl 2-(2-bromophenyl)acetate 
• 4392-24-9 Cinnamyl bromide 
• 844857-43-8 4-(2-bromobenzyl)-1,7-bis(trimethylsilyl)-1,6-heptadiyn-4-ol 
• 953780-76-2 4-(2-bromobenzyl)-1,6-heptadiyn-4-ol 
• 953780-80-8 4-(2-bromobenzyl)-1,7-diphenyl-1,6-heptadiyn-4-ol 

Downstream Products

• 844857-51-8 (R,E,E)-4-benzylidene-2-(3-phenyl-2-propenyl)-1,2,3,4-tetrahydro-2-naphthalenol 

Relevant academic research and scientific papers

Zinc-mediated α-regioselective Barbier-type cinnamylation reactions of aldehydes, ketones and esters

We report a simple, efficient, and general method for the zinc-mediated regioselective cinnamylation of aldehydes and ketones under Barbier-type conditions in a one-pot synthesis affording the corresponding α-cinnamylated alcohols in moderate to excellent yields. Compared to the literature procedures, this approach is operationally simple, uses simple reactants, and provides direct access to linear α-cinnamylated alcohols with excellent regioselectivity. Experimental results suggest that the reactions proceed through the radical pathway. In addition, the reaction was found to be scalable to the gram-scale and the one-pot protocol is also applicable to less reactive esters leading to bishomoallylic alcohols which were valuable intermediates for desymmetrizing intramolecular Heck cyclization, allowing for the elaboration to functionalized building blocks.

Oxygen donor-mediated equilibration of diastereomeric alkene-palladium(II) intermediates in enantioselective desymmetrizing heck cyclizations

This investigation examines the origin of enantioselection in the desymmetrization of an acyclic prochiral Heck cyclization precursor. High asymmetric induction (97-98% ee) is attributed to a temporary interaction of a Lewis basic oxygen donor with weakly Lewis acidic palladium(II). A series of control experiments combined with quantum-chemical model calculations provided sound evidence for a mechanism involving oxygen donor-mediated, rapid equilibration of diastereomeric alkene-palladium(II) complexes prior to the selectivity-determining ring-closing event, a Curtin-Hammett scenario. Our study also highlights the importance of the cationic pathway (triflate counter anions versus halido ligand) and alkene stereochemistry (E versus Z) in asymmetric Heck reactions.