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Directed remote aromatic metalations are useful synthetic transformations allowing for rapid regioselective access to elaborate highly substituted carbocyclic aromatic and heteroaromatic systems. This review unravels the tangle of data reported on directed remote aromatic metalations. Through a careful analysis of critically selected examples, advanced rationalizations of remote metalation regioselectivities are presented. These extend beyond the complex-induced proximity effect (CIPE). Mechanisms, driving forces, and parameters influencing remote metalations are discussed. An understanding of these metalation mechanisms enables more accurate predictability of justification of regiochemical outcomes of these useful synthetic transformations.

Directed remote aromatic metalations are useful synthetic transformations allowing for rapid regioselective access to elaborate highly substituted carbocyclic aromatic and heteroaromatic systems. This review unravels the tangle of data reported on directed remote aromatic metalations. Through a careful analysis of critically selected examples, advanced rationalizations of remote metalation regioselectivities are presented. These extend beyond the complex-induced proximity effect (CIPE). Mechanisms, driving forces, and parameters influencing remote metalations are discussed. An understanding of these metalation mechanisms enables more accurate predictability of justification of regiochemical outcomes of these useful synthetic transformations.

Inspired by nature: Angelmarin is an anticancer natural product with potent antiausterity activity, that is, selective cytotoxicity towards nutrient-deprived, resistant cancer cells. Through structure-activity relationship studies, three analogues were identified as lead compounds for the develpoment of molecular probes for the investigation of the mode of action and biological targets of the antiausterity compounds.

An efficient 8-step enantioselective total synthesis of (+)-angelmarin, starting from commercially available umbelliferone, has been achieved. Key reactions include olefin cross-metathesis and a Shi epoxidation-cyclization sequence.

An efficient 8-step enantioselective total synthesis of (+)-angelmarin, starting from commercially available umbelliferone, has been achieved. Key reactions include olefin cross-metathesis and a Shi epoxidation-cyclization sequence.

The first total synthesis of the indole alkaloid mersicarpine is reported. Key steps include a β-dicarbonyl radical cyclization, as well as an oxidation of the benzopyrrole moiety to establish the masked 1,2-dicarbonyl functionality. An X-ray crystal structure and discussion of the 1H NMR behavior of the natural product are also presented.

Pyrroles, indoles, and surprisingly, indolines, when equipped with a pendant malonyl group on the nitrogen atom, were effective substrates in a Mn(III)-mediated oxidative cyclization reaction, yielding the 1,2-annulated products in good to excellent yields. When indole acetonitrile was used as a substrate this method provided a rapid synthesis of a tetracyclic tronocarpine subunit.

We report the synthesis and characterization of trisiloxane-terminated liquid crystals with 2-phenylpyrimidine cores that form partially bilayered SmA and SmC phases. Variable temperature measurements of smectic layer spacings by powder X-ray diffraction combined with measurements of optical tilt angles and observations of birefringence changes by polarized optical microscopy reveal that the trisiloxane end-group causes the SmA–SmC transition of these compounds to be more ‘de Vries-like’ when compared to a non-siloxane analogue. One such compound, 2-(4-(11-(1,1,1,3,3,5,5-heptamethyltrisiloxanyl)undecyloxy)phenyl)-5-(1-chlorooctyloxy)pyrimidine (3), is characterized by a maximum layer shrinkage of only 1.6% and may be considered a bona fide de Vries material.