The use of an equimolar amount of pyrrolidine and HClO4 (30 mol%) was found to be effective in promoting the conjugate addition of indoles to (E)-alpha,beta-unsaturated ketones, affording the corresponding beta-indolyl ketones in excellent yields.

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High-mass γ-ray binaries consist of a presumptive pulsar in orbit with a massive star. The intense outflows from the star can absorb radio emission from the pulsar, making the detection of pulsation difficult. In this work, we present the basic geometry and formulae that describe the absorption process of a pulsar in binary with an O/B star and apply our model to two typical and well-studied binaries: PSR B1259−63/LS 2883 and LS 5039. We investigate the influences of the equatorial disc of LS 2883 with different orientations on the dispersion measure and free-free absorption of the radio pulsation from PSR B1259−63. The observed data are consistent with the disc inserted on the orbital plane with a relatively large inclination angle. For LS 5039, due to its tight orbit, it was believed that the strong wind absorption makes detecting radio emissions from the putative pulsar unlikely. However, considering the wind interaction and orbital motion, a bow shock cavity and a Coriolis shock would be formed, thereby allowing the pulsations to partially avoid stellar outflow absorption. We investigate the dependence of the radio optical depth on the observing frequencies, the orbital inclination angle, and the wind parameters. We suppose that the presumptive pulsar in LS 5039 is similar to PSR B1259−63 with pulsed emission extending to several tens of gigahertz. In that case, there could be a transparent window for radio pulsations when the pulsar is moving around the inferior conjunction. The following deep monitoring of LS 5039 and other systems by radio telescopes at high radio frequencies might reveal the nature of compact objects in the future. Alternatively, even a null detection could still provide further constraints on the properties of the putative pulsar and stellar outflows.

This paper deals with the synthesis of a new hybrid meso-tetraarylporphyrin-cardanol with the cardanol bearing an unsaturated chain. Cardanol is a renewable, natural, widely available and relatively low-cost material obtained as a by-product of the cashew industry which provides cashew kernels for edible use. The unsaturation in the chain in the new hybrid meso-tetraarylporphyrin-cardanol leads to chemical and physico-chemical properties which are different from the saturated derivatives. The unsaturation also allows preparation of the corresponding epoxy compounds as well as self-metathesis derivatives.

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