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Precise adjustment of microstructure and handedness of chiral nanomaterials is important to regulate their properties and performance.H erein, helical 3-aminophenol formaldehyde resin (APF) nanotubes and corresponding carbonaceous nanotubes with controllable handedness and optical activity were obtained via an external metal ionmediated supramolecular co-templating method in an enantiomerically pure template system, in which an appropriate amount of Mn 2+ (Co 2+ or Ni 2+)w ith moderate coordination abilities can reverse the spatial arrangement of the phenylglycine-based amphiphilic template molecules through metal coordination. Different stacking modes of coordination complexes in disparate metal ion systems lead to diverse helical senses (diameter and pitch) of the obtained helical APF.I n addition, this coordination mode of metal intervention can be applied to other amine-based helical polymer synthesis systems,whichpaves the wayfor the design of high-quality chiral nanomaterials with satisfactory physical parameters and properties.

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Nucleophilic substitution of allylic alcohols is very important in organic synthetic chemistry, which could be used for the synthesis of bioactive pharmaceutic compounds and natural compounds. One of the most powerful and efficient methods to introduce a C-3 unit is the allylic reaction. The advantage of this synthetic approach is the retention of the C＝C bond in the product that can act as a handle for further functional group transformations. One synthetic strategy that has been often relied upon to introduce this functional group is the Tsuji-Trost reaction. However, a drawback of this method is the generation of waste products resulting from displacement of the leaving group on treating with a catalyst and/or nucleophile. Therefore, the direct allylation of allylic alcohols is considered as a green method. In this review, the latest research progress on the Lewis and Brønsted acids catalyzed intermolecular and intramolecular nucleophilic substitution for the formation of C-X (X＝C, N, O, S) bond is presented, and a variety of nucleophiles, such as aromatical compounds, carbonyl compounds, amines or sulfonamides, alcohols and so on, are discussed. Finally, the problems and difficulties in research and application of allylation are discussed and then prospective is provided.