Collect. Czech. Chem. Commun. 1981, 46, 2254-2262

Addition of 2-methylthio-5-pyrimidinol and 5-methoxy-2-pyrimidinethiol to the acetylene triple bond

Zdeněk Buděšínskýa, Miloš Buděšínskýb and Alois Švába

a Research Institute for Pharmacy and Biochemistry, 130 60 Prague 3
b Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


Reaction of 2-methylthio-5-pyrimidinol (I) with 2-methylthio-5-(2-propinyloxy)pyrimidine (II) in the presence of sodium methoxide gave cis-1,3-bis(2-methylthio-5-pyrimidinyloxy)-1-propene (IIIa) and 6-methyl-2-methylthiofuro-[3,2-d]pyrimidine (IV). On addition of I to 2-propinol cis-3-(2-methylthio-5-pyrimidinyloxy)-2-propenol (V) and the isomeric 2-(2-methylthio-5-pyrimidinyloxy)-2-propenol (VI) were formed. The latter when converted to chloro derivative VII was reacted with I to give 2,3-bis(2-methylthio-5-pyrimidinyloxy)-1-propene (VIII). From 1,3-dibromo-2-propanol and I 1,3-bis(2-methylthio-5-pyrimidinyloxy)-2-propanol (XI) was prepared which was converted to 1,3-bis(2-methylthio-5-pyrimidinyloxy)-2-bromopropane (XII) and then dehydrobrominated to a mixture of cis- and trans-1,3-bis(2-methylthio-5-pyrimidinyloxy)-1-propene (IIIa, IIIb). 5-Methoxy-2-pyrimidinethiol (XIV) reacts with 2-propinol similarly as I under formation of cis-3-(5-methoxy-2-pyrimidinylthio)-2-propenol (XV) and 2-(5-methoxy-2-pyrimidinylthio)-2-propenol (XVI). Compound I when reacting with 1-chloromethyloxirane gives both 1,2-epoxy-3-(2-methylthio-5-pyrimidinyloxy)propane (X) and 1-chloro-3-(2-methylthio-5-pyrimidinyloxy)-2-propanol (XIII), depending on reaction conditions.