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The stereoselective formation of 5 contiguous chiral centers in a single pot reaction is demonstrated using an aldol, aldol-Tishchenko reaction of N-tert-butyl sulfinimines. One diastereoisomer (from 32 possibilities) predominates, and a series of cyclic and acyclic 3-amino-1,5-diol derivatives are synthesized in good yields (up to 80%) and excellent diastereoselectivities (up to >98:2 dr). Investigations support two reversible aldol steps, and multiple intermediates which are funnelled through a remarkably selective, irreversible, Tishchenko reduction, in a Curtin-Hammett phenomenon. DFT calculations using a disolvated (THF) model reveal the factors controlling stereoselectivity in the final irreversible Tishchenko step.

Density functional theory computations have elucidated the mechanism and origins of stereoselectivity in McGlacken's aldol-Tishchenko reaction for the diastereoselective synthesis of 1,3-amino alcohols using Ellman's t-butylsulfinimines as chiral auxiliaries. Variations of stereochemical outcome are dependent on the nature of the ketone starting materials used, and the aspects leading to these differences have been rationalized. The intramolecular hydride transfer step is the rate- and stereochemistry-determining step, and all prior steps are reversible.

To investigate how the long-term application of inorganic fertilizer and organic amendments affects the turnover rates of organic matter in physico-chemically fractionated components in paddy soils and how their rates are related to their amounts, we studied the effect of variable management of inorganic fertilizer and organic amendments for > 50 years on the ∆14C values of accumulated soil organic carbon (SOC) in fractionated components of 5 soil samples from three paddy fields. SOC was fractionated into four components based on their physico-chemical properties: (1) light fraction (LF) derived from plant residues, (2) heavy fraction (HF) containing stable aggregates, (3) oxidizable fraction (OxF) and (4) non-oxidizable fraction (NOxF) forming organo-mineral complexes with fine-textured minerals. The ∆14C values were determined by accelerator mass spectrometry using graphitized samples. The ∆14C values of SOC in NOxF (from −305‰ to − 90.5‰) were much lower than those of HF (from −123‰ to − 3.7‰) and OxF (from −215‰ to 21.0‰). Lowest values for NOxF suggested slowest turnover rates as expected, and higher and comparable values for OxF and HF implied much faster turnover rates of SOC in OxF compared with upland soils. This could be one of the characteristics of SOC dynamics in paddy soils, probably reflecting repeated puddling of plow layer soils. ∆14C values in all the fractions increased in response to the application of inorganic fertilizer and organic amendments, suggesting faster turnover rate. Soils with clayey and weathered characteristics had the lowest ∆14C values, or slowest turnover rates among the study fields. The relationship between the ∆14C value and the amount of accumulated C for HF, OxF and NOxF indicated that the more the SOC accumulated, the faster the turnover rate of the SOC was, regardless of the fractions, and the relationship of the HF was considerably different from those of OxF and NOxF. In conclusion, these results can be the basis for understanding the C dynamics and for improving soil fertility status and soil C sequestration in paddy soils. [ABSTRACT FROM AUTHOR]

Many studies have discussed how motivation in task‐related groups is affected by culture. Despite this, the psychological processes underlying these cultural differences have not yet been fully investigated. This study examined the effects of self‐construal on social compensation, that is, motivation gain caused by the expectation of coworkers' poor performance. Participants were 111 Japanese undergraduate students. They were asked to engage in nine tasks as a team with a coworker whose intelligence was inferior or superior and allocate tasks between themselves and their coworkers. We measured the number of tasks that participants selected as their own work as a dependent measure. The results showed that those with interdependent selves were less likely to engage in social compensation even when their coworkers' capability was low. [ABSTRACT FROM AUTHOR]

Many studies have discussed how motivation in task‐related groups is affected by culture. Despite this, the psychological processes underlying these cultural differences have not yet been fully investigated. This study examined the effects of self‐construal on social compensation, that is, motivation gain caused by the expectation of coworkers' poor performance. Participants were 111 Japanese undergraduate students. They were asked to engage in nine tasks as a team with a coworker whose intelligence was inferior or superior and allocate tasks between themselves and their coworkers. We measured the number of tasks that participants selected as their own work as a dependent measure. The results showed that those with interdependent selves were less likely to engage in social compensation even when their coworkers' capability was low. [ABSTRACT FROM AUTHOR]

Wang, K. K. Toh, E. P. J. Ng, S. Chiba, J. Am. Chem. Soc. 2011, 133, 6411 - 6421; 74 Y. Wang, S. Chiba, J. Am. Chem. Soc. 2009, 131, 12570 - 12572. 8 E. Nakamura, S. Aoki, K. Sekiya, H. Oshino, I. Kuwajima, J. Am. Chem. Soc. 1987, 109, 8056 - 8066; 9 E. Nakamura, I. Kuwajima, J. Am. Chem. Soc. 1984, 106, 3368 - 3370. Keywords: potassium; ketones; allylic alcohols; homoenolates; dianions EN potassium ketones allylic alcohols homoenolates dianions 826 833 8 03/27/23 20230321 NES 230321 This study reports the synthesis of diverse -functionalized ketones from readily available 1-arylallylic alcohols in the presence of (trimethylsilyl)methylpotassium (TMSCH SB 2 sb K). 5 E. Nakamura, H. Oshino, I. Kuwajima, J. Am. Chem. Soc. 1986, 108, 3745 - 3755; 6 E. Nakamura, I. Kuwajima, J. Am. Chem. Soc. 1983, 105, 651 - 652; 7 E. Nakamura, I. Kuwajima, J. Am. Chem. Soc. 1977, 99, 7360 - 7362. [Extracted from the article]

Full details of the theoretical study are reported on the lithium--halogen reaction of 1,1-dihaloalkenes with methyllithium and the nucleophilic substitution reaction of the resulting alpha-halo alkenyllithium compounds. The thermodynamic preferences were predicted correctly by the energy differences of the products.