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The one-pot cascade reaction for the preparation of indolizine from a wide range of chalcone, pyridine and benzyl bromide via [3 + 2] cycloaddition/oxidative aromatization promoted by Cu(OAc) 2 has been developed. This convenient method don't need to isolate the intermediates and the desired products indolizines were obtained in moderate to high yield catalyzed by Cu(OAc) 2 in the presence of oxygen. Image 1 • a one-pot manner for synthesis of indolizines derivatives, without purifying or isolating the intermediates. • The reaction doesn't require the addition of starting materials stage by stage and no additional separation process was required. • It is a new method for the synthesis of the desired products indolizines in high yield with catalyzed by Cu(OAc) 2 in the presence of oxygen. [ABSTRACT FROM AUTHOR]

Null test is preferred for measuring surface error of aspheres. However for large convex aspheres, it is challenging to fabricate larger null optics. Subaperture stitching is hence introduced but requires different null optics for subapertures of different off-axis distances. It gets easier by using replaceable computer generated holograms (CGHs). In this paper, a convex high-order even asphere is taken as an example and multiple CGHs are designed for null test of different subapertures. The same transmission flat and tilt carrier are used to facilitate alignment of CGHs. Disturbance orders of diffraction are confirmed to be separated by the tilt carrier without ghost interference. A configuration-based stitching algorithm is applied to successfully retrieve the full aperture surface error. The CGH substrate error is calibrated out before stitching optimization by measuring its transmitted wavefront with a high precision reference flat. Finally, the stitching result is verified by through-the-back null test of the same asphere. • Measurement of large convex aspheres with null subaperture stitching. • Different subaperture aberrations compensated by replaceable multiple CGHs. • Tilt carrier designed for separation of disturbance orders of diffraction. • CGH substrate error calibrated out before stitching optimization. • Experimental cross test of an even asphere with through-the-back test. [ABSTRACT FROM AUTHOR]