Unsubstituted cyclic imides were synthesized from a series of cyclic anhydrides, hydroxylamine hydrochloride (NH2OH.HCl), and 4-N,N-dimethylamino-pyridine (DMAP, base catalyst) under microwave irradiation in monomode and multimode microwaves. This novel microwave synthesis produced high yields of the unsubstituted cyclic imides for both the monomode (61 - 81%) and multimode (84 - 97%) microwaves.

The one-pot four-component reaction of benzohydrazide (2-picolinohydrazide), acetylenedicarboxylate, isatins and malononitrile (ethyl cyanoacetate) with triethylamine as base catalyst afforded functionalized 1-benzamidospiro[indoline-3,4'-pyridines] in good yields. (1)H NMR spectra indicated that an equilibrium of cis/trans-conformations exist in the obtained products.

A dipeptide-based urea-amide tertiary amine (DP-UAA) was shown to be an effective Brønsted base catalyst for the first asymmetric annulation reaction between 5H-thiazol-4-ones and N-itaconimides. High levels of enantioselectivity (up to 99% ee) and diastereoselectivity (>19:1 dr) were obtained for a series of spirocyclic 1,4-sulfur-bridged piperidinone-based succinimides.

Use of a base-free Pd(DMSO)(2)(TFA)(2) catalyst system enables the synthesis of six-membered nitrogen heterocycles via a Wacker-type aerobic oxidative cyclization of alkenes bearing tethered sulfonamides. Various heterocycles, including morpholines, piperidines, piperazines, and piperazinones, are accessible by this method.

The reaction of triarylantimony diacetates [Ar3Sb(OAc)2] with dialkyl H-phosphites [H-PO(OR)2] in the presence of a Pd(PPh3)4 (5 mol%) catalyst led to the formation of arylphosphonates in moderate to excellent yield under base-free conditions. This reaction is the first example of carbon-phosphorus bond formation by using an organoantimony compound as a pseudo-halide.

Two cyclopropane derivatives of N@C60 were synthesised by well-controlled Bingel reactions, in which 94% of the spin centres were retained, as confirmed by a series of quantitative electron spin paramagnetic resonance (EPR) measurements. Further study on the influence of the DBU catalyst base revealed a spin loss mechanism through a fullerene-DBU diradical.

[(Salcen)Cr(III) + Lewis base] was found to be a highly active and selective catalyst system in the [2+3] cycloaddition between epoxides and isocyanates to form 5-oxazolidinones. The reaction proceeds to high yield under mild reaction conditions and is applicable to a variety of terminal epoxides and aryl isocyanates.

New pentaerythritol tetrabromide-based chiral quaternary ammonium salts acting as organocatalysts (7a and 7b) have been prepared and used as organocatalysts for enantioselective Michael addition reactions between various nitroolefins and Michael donors (malonates) under mild reaction conditions, such as lower concentration of base and catalyst and room temperature, with very good chemical yield...

beta-Glucosidase from Flavobacterium meningosepticum (Fbgl) (also known as Chryseobacterium meningosepticum) has been classified as a member of the family 3 glycohydrolases. It is a retaining enzyme involving a two-step, double-displacement mechanism. D247 was shown to function as the nucleophile of the enzymatic reaction [Li, Y.-K., Chir, J., and Chen, F.-Y. (2001) Biochem. J. 355, 835-840]. H...

By employing a chiral Lewis base as the catalyst, enantioselective hydrosilylation of N-(1,2-diarylethylidene)arylamines was realized. The reactions proceeded smoothly to afford various chiral 1,2-diarylethanamines with good yields (up to 99%) in good enantioselectivities (up to 98%). Furthermore, one of the products was employed in the synthesis of a pharmaceutical substance.