Abstract: The present disclosure relates to an asymmetric process for preparing nicotine without protection, in particular to a process for preparing optically pure nicotine by taking nicotinate as a starting material and carrying out four-step reaction. The process comprises the following steps: nicotinate and ?-butyrolactone are subjected to condensation reaction, asymmetric catalytic reduction reaction, activation, and reaction with methylamine to give optically pure nicotine. The asymmetric catalytic reduction for preparing the chiral alcohol intermediate compound with high optical activity is a key step of the method.

Abstract: A sacubitril intermediate, a preparation method therefor, and use thereof. A key intermediate N-Boc amino alcohol represented by formula (10) or formula (10-a) can be efficiently prepared. The intermediate can be used to prepare a neutral endopeptidase (NEP) inhibitor or a prodrug thereof, particularly a NEP inhibitor comprising a skeleton of ?-amino-?-biphenyl-?-methylalkanoic acid or ester, such as sacubitril. Also provided are intermediates for preparing formula (10) or formula (10-a).

Abstract: The present invention relates to a preparation method of chiral primary amine. The chiral primary amine is prepared through a one-pot method that under the action of a ruthenium-chiral diphosphine catalyst, a simple ketone and an ammonium salt RCOONH4 have reductive amination by adding hydrogen and then are heated and hydrolyzed by adding acid.

Abstract: A stacked cell and preparation method thereof. The stacked cell includes: a crystalline silicon cell; a conductive connecting layer located on a surface of the crystalline silicon cell; a first isolation layer extending from a surface of the conductive connecting layer facing away from the crystalline silicon cell to penetrate through the conductive connecting layer, and a perovskite cell located on the surface of the conductive connecting layer facing away from the crystalline silicon cell.

Abstract: Disclosed are a chiral multidentate ligand (I), a preparation, and an application thereof. In this method, compound (M1) is subjected to condensation with compound (M2) followed by amine deprotection in the presence of a deprotection reagent to obtain compound (M4). Compound (1) is subjected to deprotonation by butyl lithium and phosphorization followed by dimethylamino group substitution to produce compound (3). The compound (3) and the compound (M4) are reacted in the presence of triethylamine to produce chiral multidentate ligands.

Abstract: A method for preparing nicotine. (1) The nicotinic acid alkyl ester and N-methylpyrrolidone are subjected to a condensation reaction, and then added with a strong acid to obtain 4-methylamino-1-(3-pyridine)-butanone hydrochloride. (2) The 4-methylamino-1-(3-pyridine)-butanone hydrochloride is reacted with an amino-protecting reagent to obtain an intermediate (4). (3) A chiral alcohol (5) is obtained through an asymmetric reduction. (4) The chiral alcohol (5) is converted into the nicotine through a two-step reaction.

Abstract: The present invention relates to a preparation method of chiral primary amine. The chiral primary amine is prepared through a one-pot method that under the action of a ruthenium-chiral diphosphine catalyst, a simple ketone and an ammonium salt RCOONH4 have reductive amination by adding hydrogen and then are heated and hydrolyzed by adding acid.