Carboxylic acids are widely used in the production of fine chemicals. This study demonstrates rapid synthesis of carboxylic acids directly from alcohols in microdroplets by paper spray ionization under UV irradiation. Oxidation acceleration was contributed from paper substrate as a thin film format and microdroplets of smaller sizes by paper spray ionization. Yields can reach as high as 100% for all tested alcohols except 4-nitrobenzene alcohol (39%) in microdroplets compared to 1–10% for acids and 2–50% for aldehydes with methylbenzoate byproducts in bulk phase. Preparative paper spray ionization for scaling-up syntheses realized rates of 19 mg h–1. Paper spray-based synthesis not only possesses all merits of microvolume synthesis by electro- and sonic spray, but also owns unique properties of no need for phase-transfer catalysts, and high ease to salt deposition typically occurred at the capillary tips for the latter. All these merits indicate it is a high-efficiency green methodology.

Because of their unique properties and high biological activities, organophosphorus compounds have been used worldwide in agricultural, industrial, medicinal, and veterinary applications. Conventional strategies for direct phosphonylation suffer from the usage of stoichiometric or excessive metallic or nonmetallic catalysts and long reaction times under harsh conditions, leading to a strong desire for environment-friendly protocols for phosphonylation. A protocol for the accelerated phosphonylation of N-phenyltetrahydroisoquinolines in minutes was developed without the use of any catalyst in microdroplets. The phosphonylation process was completed (>85% yields) in 10 min at 40 °C using 0.8 equiv 2,3-dicyano-5,6-dichlorobenzoquinone as the oxidant and acetonitrile as the solvent. The microdroplet phosphonylation strategy showed good suitability to alkyl phosphites and N-phenyltetrahydroisoquinolines bearing electron-withdrawing and electron-donating substitutes, and the yields of the microdroplet reaction were much greater than those of the bulk (accelerated by two orders of magnitude from the ratio of the rate constants using the microdroplet and the bulk method). Furthermore, microdroplet phosphonylation can be scaled up to a 1-phenyl-2-dimethylphosphonite-1,2,3,4-tetrahydroisoquinoline amount of 510 mg h–1 by spraying 0.1 mol L–1 N-phenyltetrahydroisoquinoline at 300 μL min–1. These figures of merit make it a promising alternative to classic organic methodologies for the synthesis of organophosphorus compounds.

Suzuki–Miyaura cross-coupling is one of the most powerful strategies for constructing biaryl compounds. However, classic Suzuki–Miyaura coupling suffers from hour-scale reaction time and competitive protodeboronation. To address these problems, a mild nonaqueous potassium trimethylsilanolate (TMSOK)-assisted Suzuki–Miyaura coupling strategy was designed for the microsynthesis of biaryls in paper spray ionization (PSI). Due to the acceleration power facilitated by microdroplet chemistry in reactive PSI, the microsynthesis of biaryls by reactive PSI was accomplished within minutes with comparable yields to the bulk, showing good substrate applicability from 32 Suzuki–Miyaura reactions of aryl bromides and aryl boronic acid/borates bearing different substituents. Based on the above TMSOK-assisted Suzuki–Miyaura coupling strategy, we further developed a high-sensitivity and selective PSI mass spectrometry (MS) method for quantitative analysis of aryl bromides, a class of environmentally persistent organic pollutants that cannot be directly detected by ambient mass spectrometry due to their low ionization efficiency. In situ derivatization of aryl bromides was achieved with aryl borates bearing quaternary ammonium groups in PSI. The proposed PSI-MS method shows good linearity over the 0.01–10 μmol L–1 range with low detection limits of 1.8–4.8 nmol L–1 as well as good applicability to the rapid determination of six aryl bromides in three environmental water samples. The proposed PSI-MS method also shows good applicability to brominated flame retardants (polybrominated diphenyls/diphenyl esters). Overall, this study provides a simple, rapid, low-cost, high-sensitivity, and high-selectivity strategy for trace aryl bromides and other brominated pollutants in real samples with minimal/no sample pretreatment.

Abstract.A large-scale complex project, which has the characteristics of a long time limit, large scale and great investment, needs the cooperation from many parties so that it can be achieved effectively. Selecting cooperative partners scientifically is the point to form a strategic alliance and carry out a project smoothly owing to the complexity and particularity of the large-scale complex project.This paper puts forward the evaluation index system for cooperative partners in strategic alliance of large-scale complex project, and establishes the grey relational model based on the combined weight by using the information entropy and AHP method.