Lignin derivative vanillin when coupled with diamines and diethyl phosphite followed by reaction with echichlorohydrin yields high-performance flame retardant epoxy resins. Biorenewable and environment-friendly flame retardant alternatives to bisphenol A epoxy resins (having plenty of applications such as coatings, adhesives, composites, etc.) have captured great attention due to their ecological and economic necessity. Vanillin, an industrial scale monoaromatic compound from lignin, is a promising sustainable candidate for high-performance polymers, while synthesis of diepoxies is challenging. Meanwhile, bio-based epoxy resins combining high performance and excellent fire resistance are more difficult to be achieved. In this paper, two novel bio-based epoxy monomers EP1 and EP2 were synthesized by one-pot reaction containing Schiff base formation and phosphorus–hydrogen addition between vanillin, diamines, and diethyl phosphite, followed by reacting with epichlorohydrin. Their reactivities are similar to bisphenol A epoxy resin DGEBA. After curing they showed excellent flame retardancy with UL-94 V0 rating and high LOI of ∼32.8%, which was due to the outstanding intumescent and dense char formation ability. Meanwhile, it was found that the cured vanillin-based epoxies had exceedingly high T gs of ∼214 °C, tensile strength of ∼80.3 MPa, and tensile modulus of ∼2709 MPa, much higher than the cured DGEBA with T g of 166 °C, tensile strength of 76.4 MPa, and tensile modulus of 1893 MPa; the properties of vanillin-based epoxies are easy to be regulated by using different “coupling” agentsdiaminesduring the synthesis process.

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A highly enantioselective Brønsted acid catalyzed direct synthesis of cyclic aminals from aldehydes has been developed. The methodology has been applied to the first asymmetric synthesis of several antihypertensive aminal drugs including (R)-Thiabutazide.

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Organic solar cells possess multiple desirable traits, such as low cost, flexibility, and semitransparency, which opens up potential avenues unavailable to other solar technologies, a prime example of this being window applications. For this specific application, a delicate balance between the transmission of light through the device and power conversion efficiency (PCE), dependent on the amount of light absorbed, must be optimized. Here, we report a high-efficiency semitransparent device based on a novel fullerene-free material system. Using an active layer based on the material system PBDB-T:ITIC, optimized devices exhibited PCEs exceeding 7% while also achieving an average visible transmittance (AVT) of 25%. The concurrent demonstration of high efficiency with an AVT of 25% represents a notable step forward for semitransparent organic solar cells. Additionally, the influence of the active layer thickness on the color rendering properties of these cells was studied. Optimization of the active layer thickness can lead to high-efficiency cells, with high visible transmission as well as the ability to display an image accurately.