Sulfenamides have attracted much attention for their significant role in rubber vulcanization. In this study, a continuous process to synthesize N-cyclohexyl-2-benzothiazole sulfenamide (CBS) with microfluidics was developed. The catalytic oxidation of 2-mercaptobenzothiazole (MBT) and cyclohexylamine using pure oxygen was performed in capillary microreactors with gas−liquid segmented flow. The residence time was shortened to 200 s owing to the enhancement of mass transfer in the microreactor. Reaction conditions such as flow rates, concentrations of copper acetate monohydrate and ammonia, temperatures, and pressures were systematically investigated. A high yield toward CBS of 87% was obtained. A simplified kinetic model (0 and 0.56 order with respect to MBT and pure oxygen, respectively) was established with operation in the kinetic-control region based on eliminating mass transfer resistance.

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Visuospatial working memory (VSWM) involves cortical regions along the dorsal visual pathway, which are topographically organized with respect to the visual space. However, it remains unclear how such functional organization may constrain VSWM behavior across space and time. Here, we systematically mapped VSWM performance across the 2-dimensional (2D) space in various retention intervals in human subjects using the memory-guided and visually guided saccade tasks in two experiments. Relative to visually guided saccades, memory-guided saccades showed significant increases in unsystematic errors, or response variability, with increasing target eccentricity (3°–13° of visual angle). Unsystematic errors also increased with increasing delay (1.5–3 s, Experiment 1; 0.5–5 s, Experiment 2), while there was little or no interaction between delay and eccentricity. Continuous bump attractor modeling suggested neurophysiological and functional organization factors in the increasing unsystematic errors in VSWM across space and time. These findings indicate that: (1) VSWM representation may be limited by the functional topology of the visual pathway for the 2D space; (2) Unsystematic errors may reflect accumulated noise from memory maintenance while systematic errors may originate from non-mnemonic processes such as noisy sensorimotor transformation; (3) There may be independent mechanisms supporting the spatial and temporal processing of VSWM.