91078-12-5

Upstream product

• 31525-67-4 dimethylacetal of 3-methyl-3-hydroxybutyraldehyde 
• 95-01-2 2,4-Dihydroxybenzaldehyde 
• 108-98-5 thiophenol 
• 87963-59-5 6-formyl-5-hydroxy-2,2-dimethyl-3-phenylthiochroman 
• 89-84-9 2',4'-dihydroxy-4-acetophenone 
• 54287-99-9 5-hydroxy-2,2-dimethyl-2H-chromene-6-carbaldehyde 
• 65490-08-6 2-hydroxy-4-(methoxymethoxy)acetophenone 
• 91078-11-4 5-Methoxymethoxy-2,2-dimethyl-3-phenylsulfanyl-chroman-6-carbaldehyde 

Downstream Products

• 111492-46-7 3-(2-hydroxy-4-methoxymethoxyphenyl)-1,1-dimethoxy-2-(5-methoxymethoxy-2,2-dimethyl-3-phenylthiochroman-6-yl)-propan-3-one 

Relevant academic research and scientific papers

Synthesis of the Phytoalexin (+/-)-Phaseollin: 3-Phenylthiochromans as Masked 2H-Chromenes and o-Prenyl Phenols

Phenylthiyl radicals are shown to add regiospecifically to 2H-chromenes to afford 3-phenylthiochromans (8), (10), (13), (14), and (15).The sulphide (15), as equivalent to a chromene protected against acid and oxidation, has been used in two syntheses of (+/-)-phaseollin, a major phytoalexin of beans and other legumes, via the sequence (17)->(18)->(19)->(20)->(21)->(+/-)-(1) or (19)->(22)->(23)->(+/-)-(1).Also the 3-phenylthiochromans, on electron transfer from metal naphthalenide or a mercury cathode, open to o-prenylphenols, providing a two step route to biogenetically important phenols from chromenes which is tolerant of free phenol and carbonyl functions and trisubstituted double bonds.

SYNTHESIS OF (+/-)-PHASEOLLIN; A PROTECTIVE SEQUENCE FOR CHROMEN DOUBLE BONDS

(+/)-Phaseollin, an important phytoalexin, has been synthesised, using as key step thallium III induced rearrangement of chromenochalcone (6) and proceeding via (8).The chromene double bond can be efficiently protected from thalliation by regioselective radical addition of thiophenol.An alternative route to phaseollin is given, through (12)-(14)-(1), with regeneration of the double bond by pyrolysis of the sulphoxide of (15).