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In maritime communications, the ubiquitous Morse lamp on ships plays a significant role as one of the most common backups to radio or satellites just in case. Despite the advantages of its simplicity and efficiency, the requirement of trained operators proficient in Morse code and maintaining stable sending speed pose a key challenge to this traditional manual signaling manner. To overcome these problems, an automatic system is needed to provide a partial substitute for human effort. However, few works have focused on studying an automatic recognition scheme of maritime manually sent-like optical Morse signals. To this end, this paper makes the first attempt to design and implement a robust real-time automatic recognition prototype for onboard Morse lamps. A modified k-means clustering algorithm of machine learning is proposed to optimize the decision threshold and identify elements in Morse light signals. A systematic framework and detailed recognition algorithm procedure are presented. The feasibility of the proposed system is verified via experimental tests using a light-emitting diode (LED) array, self-designed receiver module, and microcontroller unit (MCU). Experimental results indicate that over 99% of real-time recognition accuracy is realized with a signal-to-noise ratio (SNR) greater than 5 dB, and the system can achieve good robustness under conditions with low SNR. [ABSTRACT FROM AUTHOR]

An efficient approach to synthesize benzosiloline has been developed using a visible light-promoted radical cyclization reaction of silicon-tethered alkyl iodide and phenyl alkyne. [ABSTRACT FROM AUTHOR]

A [1,5]-anionrelay has been achieved in 3,3-bis(silyl) benzylenol ether. Deprotonation at the sterically more accessible benzylposition triggers an intramolecular proton transfer to generate thethermodynamically more stable 3,3-bis(silyl) allyloxy lithium. This endo-oriented allyl anion is stable at −78 °Cand undergoes diastereoselective syn-addition atthe γ-position with aldehydes and ketones to give monobenzyl-substituted1,2-diols. [ABSTRACT FROM AUTHOR]

An unusual [1,5]-Brook rearrangement of the lithium alkoxide of geminal bis(silyl) homoallylic alcohol is described. The unique steric and electronic effects of geminal bis(silane) were found to be crucial for promoting this long-range silyl migration, as well as for facilitating the subsequent γ/Z-selective addition of silyl allyllithium with carbonyl compounds to synthesize diverse configurationally defined Z-vinylsilanes. [ABSTRACT FROM AUTHOR]

The article presents chemical equation for the article "Visible Light-Promoted Radical Cyclization of Silicon-Tethered Alkyl Iodide and Phenyl Alkyne. An Efficient Approach to Synthesize Benzosilolines" by X. Lin and others, published in the journal "Chemical Communications" in 2016.

Due to the unique steric effect of di(silyl)methyl (DSM) groups, an exo-selective intermolecular Diels-Alder reaction of geminal bis(silyl) dienes with α,β-unsaturated carbonyl compounds is achieved. [ABSTRACT FROM AUTHOR]

The reaction proceeds via [1,5]-anion relay in 3,3-bis(silyl) benzyl enol ether. [ABSTRACT FROM AUTHOR]

Boron-containing compounds are essential micronutrients for animals and plants despite their low-level natural occurrence. They can strengthen the cell walls of the plants and they play important role in supporting bone health. However, surprisingly, boron-containing compounds are seldom found in pharmaceutical drugs. In fact, there are no inherent disadvantages reported so far in terms of the incorporation of boron into medicines. Indeed, drugs based on boron-containing compounds, such as tavaborole (marked name Kerydin) and bortezomib (trade name Velcade) have been investigated and they are used in clinical treatment. In addition, following the advanced development of boron neutron capture therapy and a new emerging proton boron fusion therapy, more boron-containing medicinals are to be expected. This review discusses the current status and perspectives of delivery strategy for boron-containing drugs., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The unique steric effect of geminal bis(silane) [(R3Si)2CH] allows an exo-selective intermolecular Diels-Alder reaction of geminal bis(silyl) dienes with α,β-unsaturated carbonyl compounds. The approach shows good generality to form ortho-trans cyclohexenes in good yields with high exo-selectivity and high enantioselectivity in some asymmetric cases. The excellent exo-stereocontrol aptitude of (R3Si)2CH group is highlighted by comparing with R3SiCH2 and R3Si groups, which leads to endo-selectivity predominantly. The conformational analysis of dienes suggests that (R3Si)2CH group effectively shields both sides of the diene moiety, ensuring the desired exo-selectivity. Moreover, the geminal bis(silane) can be further functionalized to transform the resulting ortho-trans cycloadducts into useful synthons, which makes the approach hold great potential for organic synthesis.

A regioselective 1,4-hydroiodination of dienyl alcohols has been developed using trimethylsilyl iodide as Lewis acid and iodide source. A range of homoallylic alcohols containing a multisubstituted Z-alkene was synthesized with good to excellent configurational control. The approach was applied in sequential hydroiodination/Prins cyclization to afford multisubstituted tetrahydropyrans diastereoselectively.

Bissilyl enal, prepared by a Mannich reaction of 3,3-bissilyl aldehyde with formaldehyde, has proven to be a useful linchpin in an efficient three-component coupling process. The reaction features a [1,4]-Brook rearrangement to generate the silylallyl anion, which adopts a predominant endo-orientation and can undergo addition to electrophiles in a regio- and stereoselective manner, giving various E-vinylsilane species in good yields., (© 2011 American Chemical Society)