196600-55-2

Upstream product

• 196600-19-8 (E)-2-[5-(2,5-dimethoxy-3,4,6-trimethylphenyl)-3-methylpent-2-en-4-yn-1-yl]oxytetrahydropyran 
• 131426-03-4 1-iodo-2,5-bis(methoxy)-3,4,6-trimethylbenzene 
• 4537-09-1 1,4-dimethoxy-2,3,5-trimethyl-benzene 
• 6153-06-6 (E)-3-methylpent-2-en-4-yn-1-ol 
• 41967-81-1 (E)-tetrahydro-2-<(3-methyl-2-penten-4-ynyl)oxy>-2H-pyran 
• 196600-54-1 (E)-5-(2,5-dimethoxy-3,4,6-trimethylphenyl)-3-methylpent-2-en-4-yn-1-ol 

Relevant academic research and scientific papers

Enantioselective synthesis of chromans for the preparation of enantiopure vitamin E and analogues

Coupling of the differently protected (hydroxymethyl)enynes 11 a-e and 12a-c with the iodoarene 7 in the presence of catalytic amounts of Pd(PPh3)4 afforded the arylenynes 5a-e and 6a-c which were transformed into the monoprotected chiral trihydroxy compounds 13 a-d and 14a,b by Sharpless bishydroxylation with >95% ee for 13 a-d, 91% ee for 14b, and 64% ee for 14a. A 5-step transformation of 13a led to the desired chroman derivative 3a which was cleaved to give the aldehyde 2 a known precursor for the enantioselective synthesis of vitamin E.