An organocatalytic asymmetric synthesis of a novel, highly functionalised cyclopropane system furnished with versatile substituents and containing a quaternary centre is described. The process utilises a new bifunctional catalyst based on the cinchona alkaloid framework and the products made using this catalyst were obtained as single diastereoisomers, with very high enantioselectivities (up to 96% ee). We have also demonstrated that these resulting cyclopropanes are very useful synthetic intermediates to interesting products, such as the difficult to access δ(3)-amino acids.

The nitro group is an exceptionally versatile functional group, not only because it is essentially a masked amine, but also because its chemistry can be exploited in a number of useful ways. Asymmetric organocatalysis in particular has capitalized on the use of the nitro group towards the synthesis of a variety of nitrogencontaining targets. Perhaps of greatest interest is that this functional group has been shown to be invaluable within the rapidly expanding field of organocatalytic domino reactions. This review features selected examples of nitro group reactivity in organocatalysis to demonstrate its dynamism and utility.

Review: 115 refs.

 3 -Amino Acids. -The cyclopropanation of cyanosulfones (I) in the presence of a new cupreine catalyst (PQN) gives rise to chiral cyclopropanes (III). The magnesium-mediated desulfonylation of derivative (IIIa) is accompanied by a ring opening to afford nitrile (IV), which is converted into  3 -amino acid (VI) (yield of the reduction step is not given). The borane-mediated reduction of the nitrile group of compound (IIIa) is accompanied by cyclization to afford fused pyrrolidine (VII). -(AITKEN, L. S.; HAMMOND, L. E.; SUNDARAM, R.; SHANKLAND, K.; BROWN, G. D.; COBB*, A. J. A.; Chem. Commun. (Cambridge) 51 (2015) 70, 13558-13561, http://dx.doi.org/10.1039/C5CC05158D ; Sch. Chem., Food Pharm., Univ. Reading, Whiteknights, Reading, Berkshire RG6 6AD, UK; Eng.) -R. Staver 01-029