10128-60-6Relevant articles and documents
SYNTHESIS OF 5,5'-METHYLENEBISPYRIMIDINE DERIVATIVES AND 3,4-DITHIA(6.1)(1.5) PYRIMIDINOPHANE
Kinoshita, Toshio,Tanaka, Hirokazu,Furukawa, Sunao
, p. 1809 - 1813 (2007/10/02)
Convenient syntheses of 3,6-dimethyl-1,3-oxazine-2,4(3H)-dione (3) and 5,5'-methylenebis(1-(2-hydroxyethyl)-3,6-dimethyl-2,4(1H,3H)-pyrimidinedione (5) are described.Compound 3 was prepared by the reaction of N-methylurethane with diketene, followed by alkali treatment, and 5 was obtained by treatment of 1-(2-hydroxyethyl)-3,6-dimethyl-2,4(1H,3H)-pyrimidinedione (4) with paraformaldehyde and hydrochloric acid in quantitative yield.Bromination of 5 was carried out with 47percent hydrobromic acid to give 5,5'-methylenebis(1-(2-bromoethyl)-3,6-dimethyl-2,4(1H,3H)-pyrimidinedione) (6).The reaction of 6 with thiourea afforded 7 and subsequent treatment of 7 with sodium hydroxide gave 5,5'-methylenebis(1-(2-mercaptoethyl)-3,6-dimethyl-2,4(1H,3H)-pyrimidinedione) (9).Compound 9 was oxidized to 8,11,15,18-tetramethyl-3,4-dithia(6.1)(1.5)-1,2,3,4-tetrahydro-2,4-dioxopyrimidinophane (10) with iodine under conditions of high dilution.Keywords: methylenebispyrimidine; dithiapyrimidinophane; 1,3-oxazine-2,4-dione; ring transformation; diketene; N-methylurethane; N-acetoacetyl-N-methylurethane.