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High levels of diastereoselectivity are observed for benzylation of the lithium enolates of (S)-N,N′-bis-para-methoxybenzyl-3-iso-propyl-piperazine-2,5-dione, (S)-N(1)-para-methoxybenzyl-N(4)-methyl-3-iso-propyl-piperazine-2,5-dione and (S)-N(1)-methyl-N(4)-para-methoxybenzyl-3-iso-propyl-piperazine-2,5-dione. These data suggest that the high diastereofacial selectivity observed for alkylation of these diketopiperazine templates is mainly a consequence of the relay of stereochemical information from C(3) to C(6) via the influence of 1,2-torsional strain introduced by the N-alkyl substituents, rather than through minimisation of steric interactions alone. [ABSTRACT FROM AUTHOR]

An enantiopure amine tris(phenolate) ligand containing a single stereogenic center has been used to control the propeller-like chirality of a derived pseudo-C3-symmetric titanium isopropoxide complex with excellent levels of diastereocontrol. [ABSTRACT FROM AUTHOR]

A chiral pseudo-C3-symmetric titanium triflate that employs the point chirality of a single stereogenic centre to control the propeller chirality of its aryl rings has been used to catalyse an asymmetric sulfoxidation reaction. [ABSTRACT FROM AUTHOR]

A cleavable linker strategy has been used to optimise the enolate alkylation reactions of a recyclable l-tyrosine derived polymer-supported oxazolidin-2-one for the asymmetric synthesis of a series of chiral α-alkyl acids. [ABSTRACT FROM AUTHOR]

Reaction of the sodium anion of (S)-N-(α-methylbenzyl)allylamine with two equivalents of tert-butyl cinnamate results in a remarkable tandem aza-allyl conjugate addition–Michael addition–ring closure reaction, resulting in a chiral aminocyclohexane containing six new vicinal stereogenic centres with excellent levels of stereocontrol. [ABSTRACT FROM AUTHOR]

Enolates of chiral N-(α-methyl-p-methoxybenzyl)-ω-imino-esters undergo intramolecular cyclization reactions to afford (syn)-aza-anions of β-amino esters in high dr that cyclize to afford N-(α-methyl-p-methoxybenzyl)-β-lactams that can be readily deprotected to afford their corresponding cyclic NH-β-lactams, β-amino esters, or β-amino acids. [ABSTRACT FROM AUTHOR]

A versatile methodology for the asymmetric synthesis of chiral δ-lactones containing multiple contiguous stereocenters has been developed that relies on a series of Evans’ aldol, hydroxyl-directed cyclopropanation, methanolysis, and Hg(II) mediated cyclopropane ring-opening reactions for stereocontrol. [ABSTRACT FROM AUTHOR]

1,5-Diazabicyclo[4.3.0]non-5-ene (DBN) has been shown to be an effective catalyst for the regioselective Friedel−Crafts C-acylation of pyrroles and indoles in high yields. A detailed mechanistic study implies that DBN is acting as a nucleophilic organocatalyst, with the X-ray crystal structure of a key N-acyl-amidine intermediate having been determined for the first time. [ABSTRACT FROM AUTHOR]

Reaction of 2-formyl-aryl-boronic acids with 1,2-amino alcohols results in dynamic covalent self assembly to quantitatively afford tetracyclic macrocyclic Schiff base boracycles containing bridging boron–oxygen–boron functionality. [ABSTRACT FROM AUTHOR]

Reversible bicarbonate and carbonate liquidliquid ion transfer processes from aqueous solution into an organic 4-(3-phenylpropyl)pyridine phase are driven electrochemically with TPPMn(iii/ii) and shown to be facilitated over a wide pH range by 2-naphthylboronic acid (bicarbonate transfer potential −0.08 V vs.SCE; binding constant KAB= 102mol−1dm3and carbonate dianion transfer potential 0.07 V vs.SCE; binding constant KAB2= 2 × 1010mol−2dm6). [ABSTRACT FROM AUTHOR]