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The conventional electrolarynx (EL) restores the voice of people who have lost their voice, however, its voice sounds like a robot and it occupies user's one hand. Therefore, we developed a hands‐free wearable electrolarynx that improves the voice quality with the LPC residual wave as the vibration sound. Our device was able to reproduce sounds below 500 Hz, which is close to the fundamental frequency, but from 1700 Hz to 4000 Hz, the conventional EL continuously showed a frequency response closer to the spectrum of the user's vocal sound than our device. Thus, the periodic sound of the fundamental frequency band was found to be closer to human speech than individuality or sound quality. [ABSTRACT FROM AUTHOR]

A direct method for the synthesis of acridane derivatives based upon a 2:1 coupling reaction between arynes and imines was developed. The reaction proceeds through formation of transient aza- ortho-quinone methides arising from a net [2+2] cycloaddition between arynes and imines. Introduction of steric bulk into an imine carbon has proven to be vital for this facile coupling. [ABSTRACT FROM AUTHOR]

A practical and scalable nickel-catalyzed allylic stannylation of allyl acetates with Bu3SnOMe is described. A variety of acyclic and cyclic allyl acetates, even with base-sensitive moieties, undergoes the stannylation by using NiBr2/4,4′-di- tert-butylbipyridine (dtbpy)/Mn catalyst system to afford highly functionalized allyl stannanes with excellent regioselectivity and yields. Furthermore, the scope of protocol is also extended by the reaction of propargyl acetates, giving rise to propargyl or allenyl stannanes. Additionally, a unique diastereoselectivity using the nickel catalyst different from the palladium was demonstrated for the stannylation of cyclic allyl acetates. In the reaction, inexpensive and stable nickel complexes, abundant reductant (Mn), and atom-economical stannyl source were used. [ABSTRACT FROM AUTHOR]

2-Amino-4 H-chromenes were synthesized in moderate to good yields by the reaction of o-quinone methides photochemically generated from o-(dimethylaminomethyl)phenols with malononitrile. This method was applicable to the synthesis of fluorinated chromenes that were difficult to obtain by other methods. In addition, o-(hydroxymethyl)phenols could be used for the reaction in the presence of tertiary amine bases. [ABSTRACT FROM AUTHOR]

Formal hydroboration of internal alkynes proceeds regio- and stereoselectively by the use of a diboron reagent masked with 1,8-diaminonaphthalene (dan) in the presence of readily available [(Ph3P)3CuCl], leading to direct formation of diverse B-protected alkenylborons in high yield. The B(dan) moiety can also be efficiently installed into the CC double bond of alkenes to afford the respective alkylborons. [ABSTRACT FROM AUTHOR]

A formal [4+2] cycloaddition of α,α′-dichloro- ortho-xylenes with various alkynes has been developed using a low-valent cobalt catalyst. The transformation has a wide substrate scope and high functional-group tolerance and led to 1,4-dihydronaphthalenes. The formed cycloadducts were easily aromatized with MnO2 under air. A mechanistic investigation suggests that the transformation proceeds through a benzyl cobaltation of alkyne, not the classical Diels-Alder reaction of ortho-quinodimethanes. This methodology provides a straightforward and streamlined access to linearly expanded π-conjugated aromatics. [ABSTRACT FROM AUTHOR]

An aryne insertion into the FSn bond of tributyltin fluoride leads to the synchronous formation of ArF and ArSn bonds to afford diverse 2‐fluoroarylstannanes straightforwardly. The formal total synthesis of flurbiprofen by using a fluorostannylation product is also reported. [ABSTRACT FROM AUTHOR]

Regio- and stereoselective installation of boryl and stannyl moieties into a carbon-carbon triple bond of various alkynes has been achieved based on a three-component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate-tricyclohexylphosphine complex, giving diverse vic-borylstannylalkenes in a straightforward manner. Carbon-tin and carbon-boron bonds of the resulting borylstannylation product are successively transformed into carbon-carbon bonds by a Migita-Kosugi-Stille and a Suzuki-Miyaura coupling, leading to the formation of ( Z)-tamoxifen with anti-breast cancer activity. [ABSTRACT FROM AUTHOR]

Aryne–imine–aryne coupling: Two molar amounts of arynes have beEN formally inserted into carbon−nitrogEN double bonds of imines. This aryne–imine–aryne coupling reaction selectively produces acridane derivatives via intermediary gENeration of transiENt aza ‐ o ‐ quinone methides. The use of imines with steric bulk at the imine carbon, which leads to preferENtial formation of ‘outward’ aza ‐ o ‐ quinone methides, is the key for this reaction. More information can be found in the Communication by Hiroto Yoshida et   al. on page   973 in Issue 8, 2017 (DOI: 10.1002/ajoc.201700251). [ABSTRACT FROM AUTHOR]

The title reaction leads to formation of isochromanone structures, whereas reductive work-up provides diols [cf. [ABSTRACT FROM AUTHOR]

Review: ca. 50 refs. [ABSTRACT FROM AUTHOR]

Review: 29 refs. [ABSTRACT FROM AUTHOR]