Bis -l-phenylethyl amine

A breakthrough was achieved with chiral phosphoramidite (S, R, i )-18, in which a C2-symmetric (S)-binaphthyl unit and a C2-symmetric (R, R)-bis-(l-phenylethyl)-amine unit are present (Scheme 7.10), resulting in the enantioselective catalytic 1,4-addition of Et2Zn to 2-cyclohexenone (6) with >98% ee [38]. 

Preparative Methods the phosphoramidite ligand can be prepared by the nucleophilic substitution of phosphory 1 chloride (formed from the reaction of PCI3 and (S)-2,2 -binaphthol in presence of triethylamine) with (R,R)-bis(l-phenylethyl)amine. Purification recrystallization from diethyl ether/dichloro-methane. 

Next, investigation with several secondary amines 3 was conducted (Table 3). A one-portion Mannich-type reaction with 2-ethynylbenzaldehyde la, paraformaldehyde 2 and piperidine 3b was very sluggish. Therefore, a mixmre of 2 and 3b in DMF was allowed to react at rt for 1 h in the presence of CuCl before successive addition of la and 1,3-diaminopropane 8a. This stepwise addition was successful to give the desired 3,4-dihydro-2//-pyrimido[2,l-fl]isoquinoline 12f in 61% yield (entry 1). Diallylamine 3c and bis(l-phenylethyl)amine 3d showed... 

NMR spectroscopy was applied in the enantiomeric excess determination of (iV,iV-dimethyl-(2,2,2-trifluoro-l-phenylethyl)amine-C,A)palladium complexes of a-amino acids.Dunina et al. used NMR spectroscopy and a P -chiral phosphapalladacycle for the enantiomeric purity determination of a-amino acids. P NMR spectroscopy was also used in the enantiomeric excess determination of N,C o///5< -palladated complexes of P-chiral phosphines. A ferrocene-based reagent (i p,successfully designed for the chiral recognition of /3-hydroxyphosphines and the discrimination of ( )-bis(diphenylphosphino)-1,1 -binaphthyl. 

An asymmetric intramolecular Michael-aldol reaction which leads to nonracemic tricyclic cyclobutanes is performed by using TMSOTf and bis[(/f)-l-phenylethyl]amine as chiral amine. 

Treatment of ketone (69) with excess amounts of t-BuMe2SiOTf and bis[(k)-l-phenylethyl]amine ((i )-BPEA) gives tricyclic silyl aldolate (70) with moderate enantioselectivity [104]. The formation of (70) can be explained by the enol silylation to (71) followed by a tandem Michael-aldol reaction. The asymmetric induction by the chiral amine occurs in the enol silylation (Scheme 9.40). The combined use of silyl triflates and amines has been applied to an intramolecular aldol reaction for natural product synthesis [105]. 

IV-acetyl pyrrolidines and -piperidines to the corresponding diones or ketones were similarly effected [405, 406], as were conversions of diacetyl and dibenzyl piperazines to diketo componnds by the same system (Table 5.1) [407]. Methylene groups adjacent to the N atom in tertiary polycyclic amines were oxidised by RuO /aq. NaCIO j/CCl (Fig. 5.5) [408]. A large-scale oxidation of l,4-bis(2-phenylethyl) piperazine to the dione was made by RnO /aq. Na(10 )/Et0Ac [409], and RuO /aq. Na(IO )/CCl converted dialkyl or diaryl A A -dimethyladenosines to the corresponding monoamido derivatives (Fig. 5.4) [410]. 

The first catalytic enantioselective trapping of benzene oxide-oxepine equilibrium mixture with an organometallic reagent is reported. The catalyst system included copper ditriflate and (llbi )-iV,./V-bis[(lR)-l-phenylethyl]di-naphtho[2,l- l, 2 -/][l,3,2]dioxaphosphepin-4-amine. The products of the reaction with dimethylzinc were (lA,65 )-6-methyl-2,4-cyclohexadien-l-ol in 93% ee and 4-methyl-2,5-cyclohexadien-l-ol <2001CC2606>. 

The formation of keto-phosphonate structure within macromolecule leads to the removal of internal unsaturation. Triallyl cyanurate and ionizing irradiations [210] made a E-P block copolymer-PE blend thermally stable. Triallyl cyanurate increases the crosslinking density probably due to addition reactions between polymeric and allyl radicals produced by ionizing radiation. The addition of 2,2,4-trimethyl-l,2-di-hydroquinoline and bis[4(l-methyl-1-phenylethyl)pheny 1]-amine stabilized a PE-EPDM blend against heat [211]. Popov et al. [212] studied the ozone effect on PE-iPP blend. The oxidation rate was detected in relation to... 

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