Regioselective synthesis of <I>syn</I>-oximes using 3Å molecular sieves in a solventless system

Protection (and Deprotection) of Functional Groups in Organic Synthesis by Heterogeneous Catalysis

“…The acidity in CaY and MgY zeolites can be explained by the dissociation of coordinatively bound water molecules under the action of the electrostatic field associated with the divalent cations. Quite similar high yields were obtained in the protection of aldehydes and ketones as oximes by using 3-Å molecular sieves as water scavenger under solventless conditions (Table , entry 3) …”

“…Quite similar high yields were obtained in the protection of aldehydes and ketones as oximes by using 3-Å molecular sieves as water scavenger under solventless conditions (Table 26, entry 3). 257 Hajipour reported the synthesis of oximes, hydrazones, and semicarbazones of aldehydes and ketones in nearly quantitative yield under solventless dry conditions using silica gel in the presence of sodium hydroxide (Table 26, entry 4). 258,259 The reaction was very fast with both aldehydes and ketones, but competitive experiments carried out with an equimolecular mixture of an aldehyde and a ketone in the presence of hydroxylamine showed that only the aldehydic function was protected, whereas the ketone one was recovered unchanged.…”

Catalytic Effect of Wet Molecular Sieve 3Å in Dry Media on Syntheses of Oximes and 1,3-dioximes

“…Following our pursuit of finding more facile and eco-friendly procedures of group transformations, we applied dry media conditions to the preparation of mono and 1,3-dioximes. 10 The results are shown in Tables 1 and 2. The monoximes were formed in good yields; no exceptions were found under the reaction conditions.…”

Antioxidant effect of functionalized alkyl-organotellurides: a studyin vitro

“…Tellurides B and C were prepared in good yields according to our previous protocols [27][28][29][30][31] from telluride A. Finally, telluride D was prepared (65% isolated yield) from compound A by reacting with hydroxylamine hydrochloride 32 . Scheme 1 summarizes the preparation of the mentioned compounds.…”