[reaction: see text] A practical and environmentally friendly organocatalytic strategy designed to mimic the DHAP aldolases has been developed and shown to be effective in the preparation of carbohydrates and aminosugars. (S)-Proline and (S)-2-pyrrolidine-tetrazole catalyzed the aldol reaction between dihydroxy acetone variants such as 1,3-dioxan-5-one and 2,2-dimethyl-1,3-dioxan-5-one with ald...

The zwitterionic compounds Im-E-Mel [9, E S (a), Se (b), Te (c), Im 2-{1,3-diisopropyl-4,5-dimethylimidazolium}, Mel 5-{2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylide}] are obtained from the corresponding 2-chalcogeno-1,3-diisopropyl-4,5-dimethylimidazolines 8 and 5-bromo-2,2-dimethyl-4,6-dioxo-1,3-dioxan (7) in the presence of triethylamine in excellent yields. The crystal structures of the thermal...

Equilibria between carbonyl compounds and their enamines (from O-TBDPS-derived prolinol) have been examined by NMR spectroscopy in DMSO-d(6). By comparing the exchange reactions between pairs (enamine A + carbonyl B → carbonyl A + enamine B), a quite general scale of the tendency of carbonyl groups to form enamines has been established. Aldehydes quickly give enamines that are relatively more s...

Dihydroxyacetone variants have been explored as donors in organocatalytic aldol reactions with various aldehyde and ketone acceptors. The protected form of dihydroxyacetone that was chosen for in-depth study was 2,2-dimethyl-1,3-dioxan-5-one, 1. Among the catalysts surveyed here, proline proved to be superior in terms of yield and stereoselectivities in the construction of various carbohydrate ...

Mohammad Javad Poursharifi was born in 1971 in Ray City, Iran. He obtained his B.Sc. (1994) from Kharazmi University, Tehran. He then completed his M.Sc. studies in Organic Chemistry (2008) from Islamic Azad University, Saveh Branch, Iran. Currently, he is working towards his Ph.D. under the supervision of Professor Mohammad Majid Mojtahedi and Professor Mahmood M. Hashemi at Islamic Azad Unive...

In the title compound, C(10)H(20)O(4), the dioxane ring adopts a chair conformation. The tert-butyl group occupies an equatorial position, and is staggered with respect to the O atoms of the dioxane ring. In the crystal, mol-ecules are connected by O-H⋯O hydrogen-bonds into zigzag chains of R(4) (4)(8) and R(2) (2)(12) ring motifs that run parallel to the a axis.