DiethylN,N′-o-phenylenedioxamate

Abstract

Key indicatorsSingle-crystal X-ray study T = 293 K Mean '(C±C) = 0.004 A Ê R factor = 0.058 wR factor = 0.155 Data-to-parameter ratio = 19.6For details of how these key indicators were automatically derived from the article, see

EthylN-phenyloxamate

“…The two carbonyl groups are almost antiperiplanar, with a mean O8ÐC8ÐC9ÐO9 torsion angle of 173.3 (15) , in agreement with the conformation most frequently adopted by open systems. The mean C6ÐC1Ð N7ÐC8 torsion angle is 15.0 (16) , showing that the ethyl oxamate group is almost in the mean phenyl-ring plane, in contrast to the out-of-plane conformation adopted by 1,2diphenyl (Martin et al, 2002) and 1,3-diphenyl dioxamate (Padilla-Martõ Ânez et al, 2003). In spite of the planarity exhibited by the oxamate group [mean O8ÐC8ÐC9ÐO9 = 175.5 (15) ], the mean COÐCO distance of 1.543 (3) A Ê is close to the value for a Csp 3 ÐCsp 3 single bond (Dewar & Schmeizing, 1968), indicating the absence of conjugation.…”

Switching from twisted to planar oxamide molecular cavities through intramolecular three centered hydrogen bonding

“…Each conformer was geometry optimized to a local minimum and, in the case of 1b, a single point calculation was performed to obtain the atomic charges according to the Merz-Kollman-Singh scheme. Due to the close nearby of both arms, the X-ray structure of 1a 21 …”

Diethyl piperazine-1,4-diyldioxalate

“…Alkyl oxamates have been used as intermediates in the synthesis of oxamides (Toda et al, 1986) and oxamic acid derivatives which exhibit inhibitory protein tyrosine phosphatase activity (Andersen et al, 2002). Recently, oxamates derived from primary amines have been used as molecular models for the study of three-centred hydrogen bonding (Martõ Ânez-Martõ Ânez et al, 1998;Padilla-Martõ Ânez et al, 2001) and in the design of molecular clefts (Martõ Ân et al, 2002;Padilla-Martõ Ânez et al, 2003). However, reports of oxamates derived from secondary amines are scarce in the literature (Cambridge Structural Database, April 2004 Version;Allen, 2002).…”