A cost-effective, highly regioselective and metal-free version for the synthesis of indolizine derivatives by means of Tf2O-mediated cascade reaction of pyridyl-enaminones and thiophenols/thioalcohols under mild reaction conditions has been reported. Diverse electron-rich indolizine derivatives could be obtained in up to 94% yield via the selective 1,4-addition of vinyl iminium triflate tandem cyclization/aromatization, which allowed the simultaneous construction of C–N and C–S/and one example of C–Se bonds.

An economical and efficient protocol for the direct construction of amino skipped diynes through the Cu­(I)-catalyzed reaction of enaminones and terminal alkynes has been described. Different kinds of symmetrical and asymmetrical 3-amino diynes could be obtained in up to 83% yield through a one-pot reaction under mild conditions.

An efficient Tf2O‐mediated regioselective C(sp2)−H sulfenylation of enaminones has been described. Methyl sulfoxides are employed as sulfur sources to react with different types of enaminones under mild reaction conditions, providing a straightforward approach for the synthesis of β‐amino sulfides in up to 97% yield via one‐pot manner. Moreover, this sulfenylation proceeded smoothly with oxidant‐free and metal‐free.

Abstract-Orthogonal frequency-division multiplexing (OFDM)is an appropriate solution to combat inter-symbol interference (ISI) caused by multi-path propagation in wireless communications. OFDM-based wireless communication systems become more and more popular and the base-band algorithm is one of the significant parts of the systems. In this paper, we present the design and implementation of base-band algorithms for OFDM-based wireless communication systems. The results show that the designed algorithms are effective for implementation of the system.