ABSTRACT
This paper demonstrates the first highly chemoselective syntheses of various borasiloxanes from hydroboranes and silanols, achieved through catalyst-free dehydrogenative coupling at room temperature. This green protocol, which uses easily accessible reagents, allows for the obtaining of borasiloxanes under air atmosphere and solvent-free conditions.
Subject(s)
Boranes/chemistry , Silanes/chemistry , Siloxanes/chemical synthesis , Catalysis , Green Chemistry Technology , Hydrogenation , TemperatureABSTRACT
A novel coupling reaction of thiols with (2-methylallyl)germanes catalyzed by metal triflates has been developed. This reaction provides a direct and efficient method to afford thiogermanes and opens a valuable and general synthetic route for the Ge-S cross-coupling with the elimination of isobutylene as a single by-product. Scandium(iii) triflate demonstrates the highest catalytic activity among the tested triflates. All reactions were carried out under extremely mild conditions to give thiogermanes in excellent yields. This Ge-S coupling reaction shows high generality for the variety of thiols.
ABSTRACT
PIP: The authors examine trends and determinants of internal migration to Warsaw, Poland. Consideration is given to occupational and socioeconomic status of migrants, rural-urban migration, and effects of migration on marriage. (SUMMARY IN ENG AND RUS)^ieng
Subject(s)
Employment , Marriage , Population Dynamics , Social Class , Transients and Migrants , Demography , Developed Countries , Economics , Emigration and Immigration , Europe , Europe, Eastern , Poland , Population , Socioeconomic FactorsABSTRACT
PIP: The author investigates the effects of factors such as urbanization, industrialization, depopulation of rural areas, and internal deconcentration on the spatial distribution of the population of Poland. The consequences of these factors with respect to the conditions prevailing in a given period are examined (SUMMARY IN ENG, RUS)^ieng
