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In order to study a diffusive behavior of Li+ in Li intercalated graphites, we have measured muon spin relaxation (μ+SR) spectra for C6Li and C12Li synthesized with an electrochemical reaction between Li and graphite in a Li-ion battery. For both compounds, it was found that Li+ ions start to diffuse above 230 K and the diffusive behavior obeys a thermal activation process. The activation energy (Ea) for C6Li is obtained as 270(5) meV, while Ea = 170(20) meV for C12Li. Assuming a jump diffusion of Li+ in the Li layer of C6Li and C12Li, a self-diffusion coefficient DLi at 310 K was estimated as 7.6(3) × 10−11 (cm2 s−1) in C6Li and 14.6(4) × 10−11 (cm2 s−1) in C12Li. [ABSTRACT FROM AUTHOR]

Various allylic alcohols were carboxylated in the presence of a catalytic amount of PdCl2 and PPh3 using ZnEt2 as a stoichiometric transmetalation agent under a CO2 atmosphere (1 atm). This carboxylation proceeded in a highly regioselective manner to afford branched carboxylic acids predominantly. The β,γ-unsaturated carboxylic acid thus obtained was successfully converted into an optically active γ-butyrolactone, a known intermediate of ( R)-baclofen. [ABSTRACT FROM AUTHOR]

Various allylic alcohols were carboxylated in the presence of a catalytic amount of PdCl2 and PPh3 using ZnEt2 as a stoichiometric transmetalation agent under a CO2 atmosphere (1 atm). This carboxylation proceeded in a highly regioselective manner to afford branched carboxylic acids predominantly. The β,γ-unsaturated carboxylic acid thus obtained was successfully converted into an optically active γ-butyrolactone, a known intermediate of ( R)-baclofen. [ABSTRACT FROM AUTHOR]

Inthe presence of CsF, a wide range of α-substituted α-siloxysilanes were carboxylated under a CO2atmosphere (1 atm)via Brook rearrangement. A variety of α-substituents includingaryl, alkenyl, and alkyl groups were tolerated to afford α-hydroxyacids in moderate-to-high yields. One-pot synthesis from aldehydesusing PhMe2SiLi and CO2was also possible, providingα-hydroxy acids without the isolation of an α-hydroxysilane. [ABSTRACT FROM AUTHOR]

α-Amino acids are essential resources for human life and are highly useful as building blocks for organic synthesis. The core framework of an α-amino acid can be divided into three basic components: an aldehyde, an amine, and carbon dioxide (CO2). We report herein that a one-step synthesis of α-amino acids has been successfully achieved from these three basic and inexpensive chemicals with a single operation, in which the mixture of an aldehyde, a sulfonamide, and gaseous CO2 was heated at 100 °C in the presence of Bu3Sn-SnBu3 and CsF. In this one-pot sequential protocol, two important intermediates (imine and α-amino stannane) are involved and the stannyl anion generated in situ plays a crucial role, particularly for the efficient stannylation of the imine in the presence of proton sources and for promoting retrostannylation of the undesired α-alkoxy stannane owing to its high stability and tolerance of the presence of proton sources. This methodology enabled the synthesis of a wide range of racemic arylglycine derivatives in high yields. [ABSTRACT FROM AUTHOR]

Convenient and practical synthesis of N-Boc- and N-Cbz-α-amino stannanes from the corresponding α-amido sulfones was achieved. Yields of products are generally good to high because of the consequence of avoiding the isolation of unstable imine intermediates. The procedure is so simple that large-scale stannylation is possible without any difficulty. [ABSTRACT FROM AUTHOR]

Arginine vasopressin (AVP) is a neurohypophysial hormone that coordinatively regulates central socio-emotional behavior and peripheral control of antidiuretic fluid homeostasis. Most mammals, including rodents, utilize exocrine or urine-contained scent marking as a social signaling tool that facilitates social adaptation. The exocrine scent marking behavior is postulated to fine-tune sensory and cognitive abilities to recognize key social features via exocrine/urinary olfactory cues and subsequently control exocrine deposition or urinary marking through the mediation of osmotic fluid balance. AVP is implicated as a major player in controlling both recognition and signaling responses. This review provides constructive hypotheses on the coordinative processes of the AVP neurohypophysial circuits in the systemic regulations of fluid control and social-communicative behavior, via the expression of exocrine scent marking, and further emphasizes a potential role of AVP in a common mechanism underlying social communication in rodents. • Arginine vasopressin regulates systemic processes in the production of exocrine scent marking. • Central vasopressin neuronal circuits coordinatively control scent marking behavior. • Peripheral vasopressin mediates physiological mode from voiding to marking. [ABSTRACT FROM AUTHOR]