Abstract A simple one‐pot synthesis ofβ‐hydroxyallenamides is reported. This procedure entails chemo‐ and regioselective hydroboration of 3‐en‐1‐ynyl‐sulfonylamides with Cy2BH followed by homoallenylation of aldehydes to yield β‐hydroxyallenamides (up to 94% yield and >20:1 dr). Controlled synthesis of up to three continuous stereochemical elements was realized. Density functional theory (DFT) calculations suggest a concerted Zimmerman‐Traxler chair‐like transition state. Initial results suggest that enantio‐ and diastereoselective synthesis of β‐hydroxyallenamides with optically active hydroboration reagents is viable. magnified image 
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                            High‐throughput combinatorial approach expedites the synthesis of a lead‐free relaxor ferroelectric system
                        
                    
    
            Abstract Developing novel lead‐free ferroelectric materials is crucial for next‐generation microelectronic technologies that are energy efficient and environment friendly. However, materials discovery and property optimization are typically time‐consuming due to the limited throughput of traditional synthesis methods. In this work, we use a high‐throughput combinatorial synthesis approach to fabricate lead‐free ferroelectric superlattices and solid solutions of (Ba0.7Ca0.3)TiO3(BCT) and Ba(Zr0.2Ti0.8)O3(BZT) phases with continuous variation of composition and layer thickness. High‐resolution x‐ray diffraction (XRD) and analytical scanning transmission electron microscopy (STEM) demonstrate high film quality and well‐controlled compositional gradients. Ferroelectric and dielectric property measurements identify the “optimal property point” achieved at the composition of 48BZT–52BCT. Displacement vector maps reveal that ferroelectric domain sizes are tunable by varying {BCT–BZT}Nsuperlattice geometry. This high‐throughput synthesis approach can be applied to many other material systems to expedite new materials discovery and properties optimization, allowing for the exploration of a large area of phase space within a single growth. image 
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                            - Award ID(s):
- 2311573
- PAR ID:
- 10514357
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- InfoMat
- ISSN:
- 2567-3165
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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