Lactones. Part 36a. Synthesis of halolactones with methoxyphenyl ring
Marcelina Mazur , Witold Gładkowski , Czesław Wawrzeńczyk
New p-MeOC6H4CH(CH2COOH)CH=CHMe acid (I) (m.p. 81-83°C) was synthesized by condensation of p-MeOC 6H4CHO with AcMe to p-MeOC6H 4CH=CHCOMe after following redn. with NaBH4 to p-MeOC 6H4CH=CHCH(OH)Me, condensation with Me3C(OEt) 3 at 137°C and hydrolysis with aq. soin, of KOH (yield 63%) and then converted to resp. lactones II and III (X = I, Br or Cl). Acid I was reacted with I2/KI in Et2O to a mixt. of cis-II (X = I) (m.p. 92-95°C, yield 42%) and trans-II (X = I) (oil, yield 2%), with (CH2CO)2NBr in tetrahydrofurane to a mixt of cis-II (X = Br) (m.p. 106-108°C, yield 32%), trans-II (X = Br) (oil, yield 5%) and III (X = Br) (m.p. 74-77°C, yield 10%), and with (CH2CO) 2NCl in tetrahydrofurane to a mixt of cis-II (X = Cl) (m.p. 115-118°C, yield 14%), trans-II (X = Cl) (oil, yield 8%), and III (X = Cl) (m.p. 87-89°C, yield 18%). The individual lactones II and III were sepd. by column chromatog. The 1H-NMR, 13C-NMR and IR data available for all products and intermediates. Biol, activity of lactones II and III was assumed. (Figure Presented).
|Journal series||Przemysl Chemiczny, ISSN 0033-2496, (A 15 pkt)|
|Publication indicators||= 7; : 2014 = 0.157; : 2011 = 0.414 (2) - 2011=0.296 (5)|
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