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The Michael reaction of 1,3-dicarbonyls with α,β-unsaturated esters and nitriles has been carried out very efficiently, under mild and neutral conditions, in the presence of a catalytic amount of trans -hydrido( η 1 - O -enolato) ruthenium(II) complex ( 2 ), which is prepared from the reaction of Ru(cod)(cot) ( 1 ) (cod = cycloocta-1,5-diene; cot = cycloocta-1,3,5-triene) with dimethyl malonate in the presence of 1,2-bis(diphenylphosphino)ethane (dpe).

Lithium N,N-dimethylaminoborohydride (LiMe2NBH3) reduced both 3α-azidocholest-5-ene and 3β-azidocholest-5-ene in air to give the corresponding 3α-aminocholest-5-ene and 3β-aminocholest-5-ene in 98% isolated yields. Aliphatic and benzylic azides were also reduced with LiMe2NBH3 to give the corresponding amines in isolated yields ranging from 85 to 98%. The reductions were complete in 1–3 hours and required only a simple acid-base extraction to isolate the desired amines.

Lithium aminoborohydrides (LiABH3) are a new class of powerful yet selective reducing agents that reproduce, in air, virtually all of the transformations for which lithium aluminum hydride is now used. LiABH3’s can be readily prepared as solids or generated in situ, are non-pyrophoric, and liberate hydrogen only slowly with protic solvents above pH 4. LiABH3’s can be handled in dry air as easily as sodium borohydride and retain their chemical activity for at least 6 months when stored under nitrogen or dry air at 25 °C. LiABH3’s can be synthesized from any primary or secondary amine, thus allowing control of the steric and electronic environment of these reagents.

The Michael reaction of 1,3-dicarbonyls with α,β-unsaturated esters and nitriles has been carried out very efficiently, under mild and neutral conditions, in the presence of a catalytic amount of trans -hydrido( η 1 - O -enolato) ruthenium(II) complex ( 2 ), which is prepared from the reaction of Ru(cod)(cot) ( 1 ) (cod = cycloocta-1,5-diene; cot = cycloocta-1,3,5-triene) with dimethyl malonate in the presence of 1,2-bis(diphenylphosphino)ethane (dpe).

Boron (B) doping of plasma deposited silicon films have been widely studied and applied in many devices, while B-doping of germanium has been poorly reported in literature. We have reported previously about Ge:H films with low density of localized states deposited by LF plasma with optimal hydrogen dilution.This work is devoted to a study of boron incorporation and its effect on electronic properties in Ge:H films. The films were obtained by low frequency (LF) plasma deposition from GeH4+SiH4 +B2H6 mixture diluted with hydrogen. The deposition parameters were as follow: substrate temperature Ts = 300 oC, discharge frequency f= 110 kHz, pressure P= 0.6 Torr, power W= 300 W, germane flow QGeH4= 50 sccm, silane flow, hydrogen flow QH2=3500 sccm, diborane flow was varied in the range of QB2H6=0 to 20 sccm providing boron concentration in gas phase in the range of Y=0 to 4%. Composition of the films was characterized by SIMS profiling. Hydrogen bonding was studied by FTIR. Temperature dependence of conductivity measured in DC regime in vacuum thermostat was employed to study carrier transport. Optical measurements provided optical gap, sub-gap absorption and refraction index. Boron incorporation in solid film demonstrated fast increase in the range of Y = 0 to 1.4% and then increase became slower. Hydrogen concentration in the films was determined by absorption of Ge-H stretching mode at k ≈ 1870 cm−1 and it showed weak increase with change of Y from 0 to 4%. Activation energy of conductivity increased in the range of Y = 0 to 1.5% suggesting a compensation of electron conductivity, reaching maximum value Ea =0.5 eV (corresponding approximately to Eg/2) at Y= 1.5%. Then Ea reduced to minimum value Ea = 0.27 eV at Y= 3.5% showing a trend to saturation with further Y increase. This behavior is related to change of charge transport from electron to intrinsic at Y= 1.5% and further to hole transport.

Behavioral and learning disturbances have been found in mice with partial trisomy 16, a new model for Down syndrome. Basal production of cyclic AMP in the hippocampus of trisomic mice was shown to be impaired. In addition, the responses of adenylyl cyclase to the stimulation of beta-adrenoceptors with isoprenaline and of the catalytic subunit with forskolin were both severely depressed.