Reactions of perhydro-2,2'-bipyrimidines with carbonyl compounds bearing .alpha.-carbonyl functionality
作者:Donald C. Craig、Alan Doughty、Michael Kassiou、Malcolm G. MacIntosh、Roger W. Read
DOI:10.1021/jo00073a039
日期:1993.10
Treatment of perhydro-2,2'-bipyrimidine (1) with glyoxal, glyoxylic acid, and ethyl glyoxylate in MeOH yields 10b,10c-trans-4,5,9,10-tetramethoxyperhydro-3a,5a,8a,10a-tetraazapyrene (5), 1,3-diazacyclohexane-2-carboxylic acid (9) and 10b,10c-trans-5,10-dimethoxyperhydro-3a,5a,8a,10a-tetraazapyrene-4,9-dione (10), respectively, while similar treatment of 5,5,5',5'-tetramethylperhydro-2,2'-bipyrimidine (2) with glyoxal gives an inseparable mixture of 10b,10c-trans-4,5,9,10-tetramethoxy-2,2,7,7-tetramethylperhydro-3a,5a,8a,10a-tetraazapyrene (7) and an isomeric substance and reaction with diethyl oxomalonate gives ethyl 4a,4b-trans-9-hydroxy-10-oxoperhydro-4,5,8a,10a-tetraazaphenanthrene-9-carbox ylate (12) or an unequal mixture of diethyl 10b,10c-trans-4,9-dihydroxy-5,10-dioxoperhydro-3a,5a,8a,10a-tetraazapyrene-4,9-dicarboxylate (13) and diethyl 10b,10c-trans-4,10-dihydroxy-5,9-dioxoperhydro-3a,5a,8a,10a-tetraazapyrene-4, 10-dicarboxylate (14), respectively, depending upon reaction conditions. The relative configuration of substituents in 5 is determined by NOE difference experiments, and the structure of 10 is confirmed by X-ray crystallography. Formation of these compounds represents a departure from the mode of condensation of perhydro-2,2'-bipyrimidines with simple aldehydes and ketones.