ORGN 949 |
| We demonstrated that N-(1-tosyl-1-alkyl)(thio)ureas, -(thio)carbamates and -guanidines, which are readily prepared by reaction of corresponding amides with p-toluenesulfinic acid and a variety of aldehydes, are very efficient amidoalkylation reagents. We found that they easily react with various carbonyl compounds containing electron-withdrawing groups (e.g. COOR, C(O)R, C(O)NHR, CN, SR, S(O)R, SO2R, P(O)(OEt)2, etc.) at the a-position to give, as a rule, products of tosyl group substitution. Depending on structure of these products, they undergo heterocyclization either spontaneously or after treatment with suitable nucleophiles (NH3, NaBH4, N2H4, RMgBr, etc.) to produce different types of nitrogen-containing heterocycles, namely functionalized hexahydro- and 1,2,3,4-tetrahydropyrimidin-2-ones(thiones, imines), tetrahydro-1,3-oxazin-2-ones, 1,2-dihydro-3H-pyrazol-3-ones, 5,6-dihydrofuranes, 2,3,6,7-tetrahydro-1H-1,3-diazepin-2-ones, pyrroles, etc. We showed that the obtained heterocycles can serve as starting compounds for heterocyclic syntheses in a straightforward manner. |
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New Reactions and Methodology
1:00 PM-5:00 PM, Thursday, 14 September 2006 Moscone Center -- Room 133, Oral
Division of Organic Chemistry |