ChemInform Abstract: AZOLE 87. MITT. RK. VON HYDROXYLAMIN MIT MESITYLOXID

Abstract

Mesityloxid (II) reagiert mit Hydroxylaminhydrochlorid in Gegenwart von Na‐methylat in Methanol nicht zum Isoxazolin (I), sondern neben den isomer Oximen (III) bzw. (IV) entsteht das Isoxazolin (V) und das Isoxazolidin (VI) (bzw. der Methyläther).

Synthesis and in vitro anticholinesterase activity of a series of oxime N-methylcarbamates. Structure-activity relationships

“…This group has the same position in compound 30a, since the signal of the carbon of the methylene group is located at the same field (¿ch2 = 45.6). Belly et al (1972) assigned the Z-configuration to their crystalline compound (compound 33a in our study), which is in agreement with the observed chemical shift of the proton borne by the hydroxyl group (¿oh = 10.29) as the other isomer, the liquid one, has a proton resonating at lower fields (¿oh -10.58). The study of the chemical shift for the proton on the vinyl part confirms this assignment since the values obtained (¿ = 5.62 for compound 32a and ¿h = 6.00 for compound 33a) correspond to the configurations trans-trans and trans-cis determined by Buczkowski and Plenkiewicz (1970) for those oximes, their trans-cis derivative being the Z-isomer.…”

A Simple Environmentally Friendly Method for the Synthesis of Hydroxyisoxazolidine Derivatives

“…Formation hydroxyisoxazolidines in the reaction of enones and hydroxylamine was tested only by Belly (aliphatic enones, scheme 2) [28] and Mavrov and Firgang (aliphatic-aromatic enones, scheme 3). [5,29] Mavrov and Firgang tested several bases and only for NaOH observed the formation of 5-hydroxy isoxazolidine with low to moderate yield.…”

“…[1,5,[7][8][9] For the last fifty years, there have been few articles about the synthesis of hydroxyl isoxazolidines from unsaturated carbonyl compounds and hydroxylamine (or its derivatives/ analogs). [4,5,[17][18][19][20][21][22][23][24][25][26][27][28][29] The formation of 5-hydroxyisoxazolidines easily occurred in neutral pH at room temperature (in rather an anhydrous condition), few examples of 3-hydroxyisoxazolidines synthesis are also known, but only for benzohydroxyamic acid and its analogs (p-NO 2 , p-Br and 2,3,5-(CH 3 ) 3 ). Hydroxy isoxazolidines are rather unstable (decompose when exposed to light and upon heating) and undergo chain-ring tautomerism.…”

Synthesis and structure of 5-acylhydrazine-3,3,5-trimethylisoxazolidines

“…[1][2][3] If the isoxazolidine molecule contains complex functional nucleophilic substituents, qualitatively new structural possibilities appear because these functions participate in further transformations (Scheme 1). Intermolecular nucleophilic attacks of these fragments at the C=N polar bond contained in the linear structure can lead to repeated cyclization with the formation of new cyclic forms.…”