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Abstract The transition‐metal‐catalyzed Suzuki‐Miyaura cross‐coupling (SMC) reaction of organoboron nucleophiles with aryl (pseudo)halide electrophiles is a reliable method for carbon‐carbon bond formation. This reaction generally requires the use of an exogenous base to promote transmetalation process, which limits the substrate scope of the reaction due to undesired protodeboronation and functional group incompatibilities. Here, we established a base‐free SMC reaction via a conceptually different electrophilic substitution transmetalation (EST). This transformation is applicable to a wide range of base‐sensitive and sterically hindered organoborons. Key to this advance is the formation of a stable cationic palladium(II) or nickel(II) intermediate via experimental and theoretical investigations. In a broader context, this research further expands the synthetic boundary of cross‐coupling chemistry. 

Cretaceous eolian deposits provide evidence of variations in the tropical-subtropical atmospheric circulation under greenhouse conditions. However, the misinterpretation of many such deposits as fluvial or deltaic originally hindered precise paleoclimatic reconstructions. Here we report a newly identified Early Cretaceous desert in the Hami Basin, China, which helps understand spatial-temporal variations in aridity and atmospheric circulations within central East Asia during the Early Cretaceous. The Liushuquan Formation is composed of >300-m-thick eolian deposits interpreted as an intermontane erg environment. Paleocurrent indicators within the straight-crested dunes of the Liushuquan Formation yield a mean trend of 101.3° (± 10.1°, 1 standard deviation) throughout the formation, consistent with near-surface westerly winds. Paleo-atmospheric circulation superimposed on topographic effects led to widespread eolianite accumulation during the Early Cretaceous. Combined with the spatiotemporal changes in desert distributions and prevailing surface wind patterns in East Asia, these observations are consistent with the migration of the subtropical high-pressure belt during the Early Cretaceous. We propose the following paleo-atmospheric model: (1) During the late Berriasian−Valanginian, the subtropical high belt drifted southward and northward over shorter time scales within the spatial domain of the paleo-Ordos Basin, then shifted southward at least past the Ordos Basin; (2) until the late Hauterivian−Barremian, the subtropical high-pressure zone was primarily located between the northwestern Tarim Basin and the Ordos Basin; and (3) a significant southward shift of the subtropical high-pressure zone occurred during the Aptian−Albian. 

Abstract Droplet microreactors have gained significant attention as confined spaces for chemical reactions, offering enhanced reaction rates and control. However, the impact of mass transfer induced by chemical feeding within these microreactors remains largely unexplored. In this study, a novel approach is demonstrated using liquid crystal (LC) phase transitions to feed chemicals from a bulk LC film to droplet microreactors situated on the LC film. By manipulating LC mesophases, precise control is achieved over the solubility of chemicals within the bulk LC, enabling both in situ loading and controlled release. The results reveal that while droplet confinement inherently enhances reaction rates, the chemical feeding further improves mass transport within the droplet microreactors. This synergistic effect leads to a remarkable acceleration of chemical reactions, with conversion rates up to nine times higher than conventional bulk reactions. Furthermore, the broad applicability of this approach is demonstrated across various aldehyde reactions, the reusability of the LC films for multiple reaction cycles, and multi‐step microscale synthesis within a single droplet microreactor. These findings establish the LC system as an innovative platform for chemical feeding, substantially expanding the performance and utility of droplet microreactors for diverse chemical applications. 

Template‐assisted confinement has emerged as a versatile strategy for controlling the structure and function of liquid crystal elastomers (LCEs). By guiding mesogen alignment and polymer network formation within predefined geometries, these approaches enable LCEs with programmable actuation, optical properties, and mechanical responses. This review provides a comprehensive overview of templating methods for LCE fabrication, including planar substrates, porous scaffolds, droplet‐based confinement, colloidal assemblies, microstructured molds, fibrous templates, and direct ink writing. For each category, how the geometry, surface properties, and processing conditions influence alignment quality and material performance is highlighted. The unique capabilities and challenges associated with each method are also discussed. Finally, emerging directions such as hierarchical and reconfigurable templates, multifunctional composites, and applications in soft robotics, adaptive optics, and biomimetic systems are outlined. Overall, these insights highlight the growing potential of confinement‐guided approaches in advancing the next generation of responsive LCE materials.