-bis(2-hydroxyethyl)oxalamide (BHEOA) was subject to hydroxyalkylation with ethylene carbonate (EC). By means of instrumental methods (IR, -NMR, MALDI ToF, GC, and GC-MS), an influence of the reaction conditions on structure and compositions of the obtained products was investigated. The hydroxyalkyl and hydroxyalkoxy derivatives of oxalamide (OA) were obtained by reaction of BHEOA with 2–10-molar excess of ethylene carbonate (EC, 1,3-dioxolane-2-one). The products have a good thermal stability and possess suitable physical properties as substrates for foamed polyurethanes. The obtained products were used in manufacturing the rigid polyurethane foams which possess enhanced thermal stability and good mechanical properties. 1. Introduction -bis(2-hydroxyethyl)oxalamide (BHEOA, I) can be obtained in the reaction of dialkyl oxalate or oxalic acid with 2-aminoethanol [1–3], where R = H-, CH3- lub C2H5-; see Scheme 1. Scheme 1 Apart from oxalamide (OA) itself which is very important in many branches of industry [4–9], BHEOA has found application in industry, the synthesis of polymers including. -bis(2-hydroxyethyl) derivatives of OA are used for manufacturing the flame-retardant polyurethanes [10], amide urethanes [11, 12], and also tension-resistant flexible fibers [13, 14]. The presence of oxalamide group in the structure of polymers obtained during reactions of dialkyl oxalates with polymethylenodiamines is responsible for higher strength of fibers and their better light resistance as compared to traditional polyamides [15, 16]. BHEOA was also used as a component in the flame-retardant polyurethane foams. Its presence not only decreased flammability but at the same time did not deteriorate any mechanical properties of the foamed polyurethane plastics [17]. In these studies BHEOA was subject to hydroxyalkylation with EC, and the obtained hydroxyethoxy derivatives were used for obtaining polyurethane foams of the enhanced thermal stability. 2. Experimental 2.1. Synthesis 2.1.1. Synthesis of BHEOA BHEOA was synthesized according to procedure [3]. 2.1.2. Reactions of BHEOA with EC In a 100？cm3 three-necked round bottom flask 6.6？g (0.037？mole) BHEOA and the appropriate amount of EC (pure, Fluka, Switzerland) were placed to reach the molar ratio of reagents of 1？:？2–1？:？10 and 0.31–0.47？g potassium carbonate (4.14–12.42？g/mole BHEOA, 0.03–0.09？mole/mole BHEOA), or 0.28？g diazabicyclo[2.2.2]octane (DABCO) (7.6？g/mole BHEOA, 0.06？mole/mole BHEOA) was added. The reaction mixture was protected from moisture (by tube filled with magnesium sulfate) and stirred
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