75404-02-3

Upstream product

• 75403-99-5 (2S,3S)-2-(Benzo[1,3]dioxole-5-carbonyl)-3-(3,4,5-trimethoxy-phenyl)-cyclopropanecarboxylic acid ethyl ester 
• 88775-47-7 (2E)-1-(2H-benzo[3,4-d]1,3-dioxolan-5-yl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one 

Downstream Products

• 75404-01-2 4-Benzo[1,3]dioxol-5-yl-2-[hydroxy-(3,4,5-trimethoxy-phenyl)-methyl]-4-oxo-butyric acid ethyl ester 
• 64897-38-7 1,2,3,4-tetrahydro-6,7-methylenedioxy-4-oxo-1-(3,4,5-trimethoxyphenyl)naphthalene-2-carboxylic acid 
• 64897-39-8 3-hydroxymethylpicropodophyllon 
• 64937-82-2 (5α,5aα,8aβ)-5,5a,8a,9-tetrahydro-5-(3,4,5-trimethoxyphenyl)furo<3',4':6,7>naphtho<2,3-d>-1,3-dioxole-6(5aH),9-(8aH)-dione 

Relevant academic research and scientific papers

An Improved Route to an Intermediate in Podophyllotoxin Synthesis

Cyclopropanation of the chalcone (3) with dimethylsulfonium ethoxycarbonylmethylide affords a 1:1 mixture of the cyclopropanyl keto-ester epimers (4) and (5); both stannic chloride and boron trifluoride etherate in nitromethane catalyse the stereoselective cyclisation of this mixture to the tetralone (2), the known podophyllotoxin precursor, in 51percent overall yield.