4030-10-8

Upstream product

• 78-85-3 2-methylpropenal 
• 100-52-7 benzaldehyde 
• 80997-79-1 2-phenyl-4-methylenetetrahydrofuran 
• 507260-94-8 4,4-dibromo-3-methyl-1-phenylbut-3-en-1-ol 
• 137003-82-8 3-hydroxy-3-phenylpropyltriphenylphosphonium bromide 
• 636599-04-7 4,4-dibromo-3-methyl-1-phenylbut-3-enyl acetate 

Downstream Products

• 111551-03-2 hydroxy-2 bromo-3β methyl-3α phenyl-5β tetrahydrofuranne 
• 111551-03-2 hydroxy-2β bromo-3α methyl-3β phenyl-5β tetrahydrofuranne 
• 19930-93-9 cis-1-Methyl-2-phenylcyclopropan-aldehyd 
• 175788-15-5 (2-methyl-2-(2-methylprop-1-en-1-yl)cyclopropyl)benzene 

Relevant academic research and scientific papers

Intramolecular Substitution Reaction of Lithium Alkylidene Carbenoids. Regioselective Synthesis of Indenes

When 4,4-dibromo-3-alkenols are treated with butyllithium, an intramolecular substitution reaction with alkoxide moiety occurs at the lithium alkylidene carbenoid center to give dihydrofurans. The reaction mechanism of this intramolecular substitution reaction is studied by B3LYP density functional calculations with the 6-31+G(d) basis set, and the substitution is found to proceed in a concerted manner. This substitution reaction is applied to the regioselective preparation of indene derivatives. That is, treatment of 3-(o-bromophenyl)-1,1-dibromopropene derivatives 23 with butyllithium results in the formation of intramolecular substitution intermediates, 3-indenyllithiums D, which are trapped with electrophiles to afford substituted indenes regioselectively.

Novel synthesis of methylenecyclobutanols and 4-methylenetetrahydrofurans from γ-oxide ylides

The reaction of δ-halo-γ-oxide ylide, prepared from methylenetriphenylphosphorane and epichlorohydrin, with aldehydes afforded alkylidenecyclobutanols in moderate yields. The reaction initially proceeded through internal nucleophilic attack on δ-carbon of this ylide. Another novel approach toward the synthesis of 4-methylenetetrahydrofurans was achieved by the reaction of γ-oxide ylides with paraformaldehyde.

NMR Studies of Bond Orders in Heteroaromatic Systems

Fifty-seven for the ortho-benzylic coupling constant 4JMe-C=C-H (henceforth denoted as 4JOB) were obtained for a variety of heteroaromatic systems.It was shown that a good correlation exists between 4JOB when the methyl group is not α to the heteroatom and the SCF-MO bond order.This method can therefore be used as experimental means of determining bond orders in heteroaromatic systems.An examination of bond alternation in thirteen heteroaromatic systems has given a measure of relative "degree of aromaticity" for a larger number of systems than previously r eported by any single method.