81601-99-2

Upstream product

• 1489-06-1 2,3-diphenyl-5,6-dihydropyrazine 
• 1588-89-2 2,3-diphenylpyrazine 
• 123-51-3 i-Amyl alcohol 
• 134-81-6 benzil 
• 951-87-1 rac-1,2-diphenylethylene-1,2-diamine 
• 107-21-1 ethylene glycol 
• 104-71-2 N,N'-bis(benzyliden)ethylendiamine 
• 119-53-9 2-hydroxy-2-phenylacetophenone 
• 31819-61-1 cis-5,6-diphenyl-piperazin-2-one 
• 951-87-1 meso-1,2-diphenyl-1,2-diaminoethane 
• 104-71-2 (1E,1’E)-N,N’-(ethane-1,2-diyl)bis(1-phenylmethanimine) 
• 116360-40-8 N-<(tri-n-butylstannyl)methyl>benzaldimine 
• 110-83-8 cyclohexene 
• 1609286-01-2 (R,S)-5,6-diphenylpiperazine-2,3-dione 

Downstream Products

• 1376191-63-7 (R,R)-tert-butyl-4-benzyl-2,3-diphenyl-1-piperazinecarboxylate 
• 1376189-45-5 (R,R)-1-benzyl-2,3-diphenylpiperazine 
• 1376191-29-5 (3R,4R)-8-octyl-3,4,6-triphenyl-3,4-dihydropyrrolo[1,2-a]pyrazine 
• 1376191-82-0 C₃₈H₃₄N₂ 
• 1241681-30-0 (R,R)-tert-butyl-2,3-diphenyl-1-piperazinecarboxylate 
• 81577-02-8 1,4-dibenzyl-2r,3c-diphenyl-piperazine 
• 81577-01-7 piperazine-2,3 diphenyl N,N-dimethyl cis 
• 81401-24-3 cis-2,3-diphenyl-1,4-diazabicyclo<2.2.2>octane 
• 81577-03-9 piperazine-2,3 diphenyl N,N-dimethyl trans 
• 81401-24-3 trans-2,3-diphenyl-1,4-diazabicyclo<2.2.2>octane 

Relevant academic research and scientific papers

Synthesis of chiral 2,3-disubstituted 1,4-diazabicyclo[2.2.2]octane derivatives

Racemic 2,3-diaryl-1,4-diazabicyclo[2.2.2]octane (DABCO) derivatives are synthesized from the readily accessible piperazines in 50-64% yield by cyclization using ethylene bromide, triethylamine, and KI at 80 °C. The enantiomerically enriched 2,3-diphenylpiperazine and the 2,3-bis(1-naphthyl)piperazine derivatives are prepared by a resolution method using commercially available optically active acids, yielding the corresponding DABCO derivatives in 51-64% yield with up to 99% ee. This mild cyclization can also be applied to enantiopure camphanyldiamine derivatives, and the products are obtained in 72-86% yields.

CHIRAL FLUORINATING REAGENTS

This invention relates to fluorinating agents and, more particularly, to chiral non-racemic fluorinating agents useful for enantioselective fluorination, as well as to their synthesis and use and other subject matter. The fluorinating agents are based on a substituted 1,4-diazabicyclo[2.2.2]octane (DABCO) skeleton and provide electrophillic fluorine enantioselectively.

YbCl3-catalyzed one-pot synthesis of dihydropyrazines, piperazines, and pyrazines

A simple and efficient synthetic approach to dihydropyrazines via YbCl 3-catalyzed reaction of α-hydroxyketones with diamines under mild conditions was developed. The corresponding 2,3-subsitituted piperazines and pyrazines were obtained through tandem conversion of dihydropyrazines with good yields.

Highly enantioselective synthesis of chiral allenes by sequential creation of stereogenic center and chirality transfer in a single pot operation

Chiral allenes are readily accessed in a single pot operation in the reaction of terminal alkynes, aldehydes, chiral secondary amines, and zinc halides in good yields (up to 77% yield) and excellent enantioselectivities (up to 99% ee) in toluene at 120 °C. The reaction proceeds through initial formation of chiral propargylamine intermediates with creation of a new stereogenic center and subsequent chirality transfer via an intramolecular hydride shift to produce chiral allenes with high enantiomeric purities.

A new Yb3+-catalyzed pinacol and imine-coupling reaction

Ytterbium triflate, Yb(OTf)3, catalyzes the intermolecular reductive homocouplings of imines, aldehydes, and ketones at loadings of 5 mol % in the presence of Mg and Me3SiCl to give isolated yields of up to 95%. Diastereoselectivity of up to 4/96 (dl/meso) is achieved for aromatic aldehydes, up to 100% dl for aliphatic aldehydes, and 100% dl for an intramolecular imine coupling.

A bifunctional PdVMgO solid catalyst for the one-pot selective N-monoalkylation of amines with alcohols

It has been found that a bifunctional metal Pd/base (MgO) catalyst performs the selective monoalkylation of amines with alcohols. The reaction goes through a series of consecutive steps in a cascade mode that involves: 1) the abstraction of hydrogen from the alcohol that produces the metal hydride and the carbonyl compound; 2) condensation of the carbonyl with the amine to give an imine, and 3) hydrogenation of the imine with the surface hydrogen atoms from the metal hydride. Based on isotopic and spectroscopic studies and on the rate of each elementary step, a global reaction mechanism has been proposed. The controlling step of the process is the hydride transfer from the metal to the imine. By changing the crystallite size of the Pd, it is demonstrated that this is a structure-sensitive reaction, whereas the competing processes that lead to subproducts are not. On these bases, a highly selective catalyst has been obtained with Pd crystallite size below 2.5 nm in diameter. The high efficiency of the catalytic system has allowed us to extend the process to the one-pot synthesis of piperazines.

New chiral titanium complexes for enantioselective reductive cyclizations of diimines to trans-2,3-diarylpiperazines

Enantioselective intramolecular reductive coupling of diimines by chiral titanium complexes, prepared using a titanium(IV) reagent and hemisalen ligands derived from chiral β-amino alcohols, gives trans-2,3-diarylpiperazines in up to 97% ee.

A simple method of synthesis of (±)-2,3-diarylpiperazines and a novel method of resolution of (±)-2,3-diphenylpiperazine

Intramolecular reductive coupling of diimines in the presence of Zn/Ti(OiPr)2Cl2 gives the corresponding (±)-2,3-diarylpiperazines in 73-83% yields with dl/meso ratio >99%: 1%. The (±)-2,3-diphenylpiperazine obtained in t

A facile synthesis of vicinal diamines promoted by low-valent niobium: Preparation of chiral octahydrobiisoquinolines and their application to catalytic asymmetric synthesis

An efficient homocoupling of imines to give vicinal diamines promoted by low-valent niobium, generated by treatment of NbCl5 with zinc powder, is described. The desired products were obtained in good to excellent yields. Dihydroisoquinoline derivatives also gave the coupling products with good diastereoselectivities (D,L/meso). Optical resolution of the racemic octahydrobiisoquinolines was achieved and their complexes with Cu1 used in the catalytic asymmetric oxidative coupling of β-naphthols. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.

Diastereoselective synthesis of piperazines by manganese-mediated reductive cyclization.

A simple and effective synthesis of trans aryl-substituted piperazines using a Bronsted acid and manganese(0) is described. [reaction: see text]