- Syntheses of Families of Enantiopure and Diastereopure Cobalt Catalysts Derived from Trications of the Formula [Co(NH2CHArCHArNH2)3]3+
-
Aerobic reactions of CoX2 (X = OAc, Cl) or Co(ClO4)2 with (S,S)-1,2-diphenylethylenediamine [(S,S)-dpen] in CH3OH, followed by HCl or HClO4 additions, give the diastereomeric lipophobic salts Λ-[Co((S
- Ghosh, Subrata K.,Lewis, Kyle G.,Kumar, Anil,Gladysz, John A.
-
-
Read Online
- Ultrasound accelerated reductive coupling of imine or iminium ion generated in 5m lithium perchlorate solution by lithium metal
-
A novel one-pot reductive coupling of imine or iminium ion generated in the concentrated ethereal lithium perchlorate solution was achieved in the presence of lithium metal. The yield of the reaction depends on the reactivity preformed imine or iminium ion. Diamines were formed with high diastereoselectivity in some cases in about 5 h. The reaction time was doubled without the use of ultrasound acceleration.
- Mojtahedi,Saidi,Shirzi,Bolourtchian
-
-
Read Online
- Reaction of aromatic aldehydes with ammonium acetate
-
By reaction of aromatic aldehydes with ammonium acetate a series of 1,2-diaryl-1,2-diamino-ethanes and their derivatives was obtained. The mechanism of reaction was suggested and its principal stages were proved. Reactions with ammonium acetate of aromatic aldehydes containing ortho-substituents resulted in the corresponding 2,4,5-triaryl-4,5-dihydroimidazoles.
- Proskurnina,Lozinskaya,Tkachenko,Zefirov
-
-
Read Online
- Highly diastereoselective and enantioselective addition of organometallic reagents to a chiral C2-symmetrical bisimine
-
An efficient and straightforward method has been developed for the preparation of enantiomerically enriched C2-symmetrical vicinal diamines via the addition of organometallic reagents to a chiral bisimine, which gives access to a variety of optically pure aromatic and aliphatic C 2-symmetrical vicinal diamines in high yields. The 'Cram-Davis' open transition state model is proposed to rationalize the observed stereoselectivities for the addition of organolithium reagents to the bisimine. Georg Thieme Verlag Stuttgart.
- Sun, Xiaoxia,Wang, Shuangjun,Sun, Shangjin,Zhu, Jin,Deng, Jingen
-
-
Read Online
- Diboron glycol ester as well as preparation method, intermediate and application thereof
-
The invention discloses diboron glycol ester as well as a preparation method, an intermediate and application thereof. The diboron glycol ester can be used for inducing reductive coupling reaction with imine as a substrate, and the substrate can be obtained by reaction of aldehyde and ammonia and is very easy to obtain and quite low in cost. The product can be separated from a reaction system onlyby acid-base operation without column chromatography purification, and the post-treatment mode is convenient and easy to operate. The yield of the obtained product is high, and protective group operation is not needed. The diboron glycol ester has chirality, the stereoselectivity of the reductive coupling reaction is generally excellent, and 99% ee chiral diamine can be obtained only through simple recrystallization. The diboron glycol ester can be obtained by reacting diol with diboron glycol ester, the diol is convenient to prepare and easy to amplify, the diol can be recycled from a reaction solution through simple acid-base operation, the recovery rate reaches 95%, and the preparation cost is further saved.
- -
-
Paragraph 0130-0135; 0139-0141
(2020/08/02)
-
- Enantioselective Reductive Coupling of Imines Templated by Chiral Diboron
-
We herein report a general, practical, and highly efficient method for asymmetric synthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantioselectivity and stereospecificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method signifies the generality of diboron-enabled [3,3]-sigmatropic rearrangement.
- Chen, Dongping,Li, Kaidi,Tang, Wenjun,Xu, Guangqing,Xu, Ronghua,Zhou, Mingkang
-
supporting information
p. 10337 - 10342
(2020/07/04)
-
- Method for preparing intermediate of chiral vicinal diamine
-
The invention discloses a method for preparing an intermediate of chiral vicinal diamine. The method comprises the following steps: adding a compound IV into a solvent, stirring the compound IV and the solvent in an ice water bath, adding an initiator into the obtained reaction system, adding a reducing agent into the reaction system in batches, heating the reaction system to 20-80 DEG C, and stirring the reaction system; and extracting the reaction system after the reaction is completed, drying the obtained organic phase, filtering the dried organic phase, and performing rotary drying to obtain a compound V that is the intermediate. The preparation method of the invention has the advantages of simplicity and mild reaction conditions, and can be widely applied to industrial production.
- -
-
-
- Chemoselective Photoredox Synthesis of Unprotected Primary Amines Using Ammonia
-
Unprotected α-amino carbon radicals are produced as novel intermediates via a transformation that merges acid-promoted N-H imine generation and chemoselective photocatalytic single-electron reduction. Coupling ammonia and aldehydes/ketones allows the generation of primary amines under mild conditions without the need for protecting groups. The key intermediate can be efficiently transformed into primary (di)amines by a formal dimerization, reductive amination via hydrogen atom transfer, and arylation through radical-radical coupling.
- Rong, Jiawei,Seeberger, Peter H.,Gilmore, Kerry
-
supporting information
p. 4081 - 4085
(2018/07/15)
-
- TRANSITION METAL COMPLEXES FOR ENANTIOSELECTIVE CATALYSIS OF CARBON-CARBON, CARBON-HETEROATOM, AND CARBON-HYDROGEN BOND FORMING REACTIONS
-
In some embodiments, the present disclosure pertains to a compound, comprising a transition metal complex having the formula Φ-[Μ (x,y)-L1 (w,v)-L2 (t,u)-L3]p+An-mZ-p_m. In an embodiment of the present disclosure Φ may be A. In another embodiment Φ may be Δ. In some embodiments of the present disclosure, M is a transition metal. In a related embodiment, p is an integer corresponding to the oxidation state of M. In some embodiments of the present disclosure, each of x, y, w, v, t, and u independently comprise R. In other embodiments, each of x, y, w, v, t, and u independently comprise S. In an embodiment of the present disclosure, each of L1, L2, and L3 independently is a ligand comprising a substituted diamine. In some embodiments, An" comprises a lipophilic anion, where m is from 1 to 3, and where Z- comprises an optional second anion.
- -
-
Paragraph 00107
(2014/02/16)
-
- NOVEL RUTHENIUM COMPLEX AND PROCESS FOR PRODUCING OPTICALLY ACTIVE ALCOHOL COMPOUND USING SAME AS CATALYST
-
The present invention provides: a novel ruthenium complex which has excellent catalytic activity with respect to reactivity in the reduction of a multiple bond, in particular, in the asymmetric reduction of a carbonyl compound, enantioselectivity, etc.; a catalyst which comprises the ruthenium complex; and a process for producing optically active compound, in particular, an optically active alcohol compound, using the catalyst. The ruthenium complex has a ruthenacyclic structure. The catalyst is a catalyst for asymmetric reduction which comprises the ruthenium complex.
- -
-
Paragraph 0076
(2014/03/21)
-
- SULPHONYLATED DIPHENYLETHYLENEDIAMINES, METHOD FOR THEIR PREPARATION AND USE IN TRANSFER HYDROGENATION CATALYSIS
-
A diamine of formula (I) is described, in which A is hydrogen or a saturated or unsaturated C1-C20 alkyl group or an aryl group; B is a substituted or unsubstituted C1-C20 alkyl, cycloalkyl, alkaryl, alkaryl or aryl group or an alkylamino group and at least one of X1, X2, Y1, Y2 or Z is a C1-C10 alkyl, cycloalkyl, alkaryl, aralkyl or alkoxy substituting group. The chiral diamine may be used to prepare catalysts suitable for use in transfer hydrogenation reactions.
- -
-
Page/Page column 8
(2008/06/13)
-
- Reductive coupling of aromatic oxims and azines to 1,2-diamines using Zn-MsOH or Zn-TiCl4
-
The reduction of aromatic aldoxims and azines with Zn in the presence of MsOH or TiCl4 afforded N,N′-unsubstituted 1,2-diamines in one-step. The reductive coupling with Zn-MsOH gave meso 1,2-diamines selectively, whereas dl 1,2-diamines were fo
- Kise, Naoki,Ueda, Nasuo
-
p. 2365 - 2368
(2007/10/03)
-
- Synthesis of phosphoramides for the lewis base-catalyzed allylation and aldol addition reactions
-
Both chiral and achiral phosphoramides of diverse structure were prepared from diamines by the coupling to phosphorus(V) or phosphorus(III) reagents. Several enantiopure 1,2-diphenyl-1,2-ethanediamine analogues have been prepared by the reductive coupling of the corresponding N-silylimine with NbCl4(THF)2 and subsequent resolution by the formation of diastereomeric menthyl carbamates. (S,S)-N,N'-Di-(1-naphthyl)-1,2-diphenyl- 1,2-ethanediamine 15 was prepared by the arylation of (S,S)-1,2-diphenyl- 1,2-ethanediamine with naphthyl iodide.
- Denmark, Scott E.,Su, Xiping,Nishigaichi, Yutaka,Coe, Diane M.,Wong, Ken-Tsung,Winter, Stephen B. D.,Choi, Jun Young
-
p. 1958 - 1967
(2007/10/03)
-
- Convenient Routes to Symmetrical Benzils and Chiral 1,2-Diaryl-1,2-diaminoethanes, Useful Controllers and Probes for Enantioselective Synthesis
-
Pathways for the diastereoselective preparation of chiral 1,2-diaryl-1,2-diaminoethanes from ArCOOH, ArCHO or ArBr are described.
- Corey, E. J.,Lee, Duck-Hyung,Sarshar, Sepehr
-
-
- Synthesis of Nitrogen-Containing Macrocycles with Reductive Intramolecular Coupling of Aromatic Diimines
-
Reductive intramolecular coupling of aromatic diimines is an effective method for the synthesis of a variety of nitrogen-containing macrocycles. 1,4-Diazacrown ethers 3 were effectively synthesized by intramolecular coupling of bis(imino ethers) 9 promoted by electroreduction (method A) or chemical reduction with zinc powder (method B) in the presence of methanesulfonic acid.In spite of the formation of macrocycles, the yields of 3 were relatively high.This can be explained by the formation of proton-bridged intermediates 14, in which intramolecular hydrogen bonds are formed between hydrogen and oxygen atoms of diiminium salts.Method B was more effective in the formation of 1,4-diaza-12-crown-4 derivatives 3 (n = 1) due to the template effect of Zn(2+).Optically active macrocyclic bislactones 4 were synthesized stereoselectively by reductive intramolecular coupling of bis(imino esters) 20 with zinc powder (method B).The high stereoselectivity is explained by considering proton-bridged intermediate 23.The resultant compounds 4 were transformed to optically active 1,2-diarylethylenediamines 7.Various sizes of macrocyclic bislactams 5 were synthesized by reductive intramolecular coupling of bis(imino amides) 26 with zinc powder (method B).Reduction of 5 gave the corresponding macrocyclic polyamines 6.
- Kise, Naoki,Oike, Hideaki,Okazaki, Eiichi,Yoshimoto, Masami,Shono, Tatsuya
-
p. 3980 - 3992
(2007/10/02)
-
- A novel method for stereoselective synthesis of (1R,2R)-diarylethylenediamines by reductive intramolecular coupling of aromatic diimines
-
Reduction with zinc has been found to be an effective method for selective synthesis of (1R,2R)-diarylethylenediamines from the corresponding chiral aromatic diimines through their intramolecular coupling.
- Shono, Tatsuya,Kise, Naoki,Oike, Hideaki,Yoshimoto, Masami,Okazaki, Eiichi
-
p. 5559 - 5562
(2007/10/02)
-
- 211. Scope and Limitations of the Reductive Coupling of Aromatic Aldimine Derivatives with Formation of 1,2-Diarylethylenediamine Units, Using Low-Valent Titanium Reagents
-
Besides the adducts from lithium amides to aromatic aldehydes, iminium salts, aminals, and N-silylimines of aromatic aldehydes are coupled by the black suspension obtained from TiCl4 and Mg turnings in tetrahydrofuran (THF).The 1,2-diarylethylenediamines with tertiary and primary amino groups thus obtained are formed with no or only moderate diastereoselectivity (products 4a-d (Scheme 2) and 5a-e (Scheme 3), respectively); the amine component may contain a strained ring or additional heteroatoms as in azetidin, bis(2-metoxyethyl)amine piperazine, morpholine, and thiomorpholine (products 6a-e; Table 1).By an in-situ procedure, ethylenediamines and propane-1,3-diamines with two secondary amino groups are cyclized with aromatic aldehydes to give exclusively trans-diaryl-substituted piperazine and perhydro-1,4-diazepine derivatives (products 7a-f; Table 2).Enantiomerically pure monocyclic trans,cis-5-alkyl-2,3-diaryl-piperazines and diazabicyclononanes and -decanes are obtained by employing suitable diamines prepared from the amino acids (S)-alanine, (S)-phenylalanine, (S)-proline, and from (S,S)- or (R,R)-cyclohexane-1,2-diamine, respectively (products 11a-i, 7e; Table 4).The configurations of all products are derived from the high-field NMR spectra, some of which are discussed in detail (Figs. 1 and 2, Tables 3 and 5); all new compounds are fully characterized by their physical data.Depending upon the structure of the components employed, the yields of purified products range from as low as 7percent to essentially quantitative.
- Betschart, Claudia,Schmidt, Beat,Seebach, Dieter
-
p. 1999 - 2021
(2007/10/02)
-
- N,N'-Dialkyl-1,2-bis(hydroxyphenyl)ethylenediamines and N,N'-Dialkyl-4,5-bis(4-hydroxyphenyl)imidazolidines: Syntheses and Evaluation of Their Mammary Tumor Inhibiting Activity
-
Diastereomeric N,N'-dialyl-1,2-bis(hydroxyphenyl)ethylenediamines (5) were synthesized and tested for their affinity for the estradiol receptor.Only the (+/-)-1,2-bis(4-hydroxyphenyl)ethylenediamines with the alkyl groups C3H7 a=1.1
- Angerer, Erwin von,Egginger, Guenter,Kranzfelder, Gerhard,Bernhauer, Horst,Schoenenberger, Helmut
-
p. 832 - 837
(2007/10/02)
-