The methyl diazoacetate and aryl (N-tosyl)imines can be transformed into syn or anti a-hydroxy b-amino esters with high diastereoselectivities in three steps: the base promoted nucleophilic condensation of the methyl diazoacetate and aryl (N-tosyl)imines to give b-(N-tosyl)amino a-diazoesters, followed by oxidation with Oxone to generate a-oxo esters, which were reduced with NaBH4 to yield the ...

Isatin is a heterocyclic nitrogen compound that has attracted much interest in recent years due to its diverse biological and pharmacological activities. It can be used many medical applications, such as antidiabetic, antibiotic, anticancer agents. The isatin molecule also prepared from different substrates by various methods, the methods of Sandmeyer, Stolle, Gassman, Meanwell Hewawasam others...

Chiral α-branched allylic amines are important building blocks for organic synthesis, and several catalytic asymmetric methods have been developed for their synthesis. For example, enantioselective metal-catalyzed amination of allylic electrophiles 1 , 2 , 3 ] and rearrangement of allylic imidates have proven to be highly effective. An alternative approach to chiral allylic amines that can be a...

The asymmetric catalytic Strecker reaction of achiral N-phosphonyl imines with Et(2)AlCN has been established. Both free amino alcohols and BINOLs have been proven to be effective catalysts to afford excellent enantioselectivities and yields. The N-phosphonyl group can be readily cleaved under mild conditions and enable purification of crude products by simple washing with hexane. The cleaved N...

In enzymology, as in organic chemistry, many transformations revolve around the chemistry of the carbonyl group. A carbonyl group is electrophilic how can it be made more so? Hydrogens next to a carbonyl group have a reduced pK, how can this reactivity be promoted? Nature has found several ways to address these mechanistic challenges, the most important of which is the use of imines. Studies on...

Ni(0)-catalyzed dehydrogenation of benzylic-type imines was performed to yield asymmetrical tetra-substituted imidazoles and 2-imidazolines. This was achieved with a single operational step while maintaining good selectivity and atom economy. The catalytic system shows low to moderate tolerance for fluoro-, trifluoromethyl-, methyl-, and methoxy-substituted benzylic-type imines. In addition, th...

This review is oriented toward the asymmetric transfer hydrogenation (ATH) of imines regarding mostly fundamental, yet important topics from the practical point of view. Development of analytical methods for the monitoring of ATH (i.e., kinetics and stereoselectivity) belongs to those topics, as well as studies on the influence of reaction conditions and structural variations on the reaction pe...

The default explanation for good to high diastereomeric excess when reducing N-chiral imines possessing only mediocre cis/trans-imine ratios (>15% cis-imine) has invariably been in situ cis-to-trans isomerization before reduction; but until now no study unequivocally supported this conclusion. The present study co-examines an alternative hypothesis, namely that some classes of cis-imines may ho...

An iron-catalyzed transfer hydrogenation of N-aryl and N-alkyl imines using isopropanol as the hydrogen donor is reported for the first time. A combination of two iron complexes serving different roles is the key for the success of this catalytic system. As a result, an environmentally friendly and precious metal-free transfer hydrogenation of imines has been developed. The use of a suitable co...

A selective atmospheric hydrogenation of unsaturated imines over heterogeneous iridium catalyst is described, in addition the selectivity elucidated by DFT-calculations.