Optical Resolution of (±)-1,2-Bis(2-methylphenyl)ethylene-1,2-diamine as a Chiral Framework for 2-Iminoimidazolidine with 2-Methylphenyl Pendant and the Guanidine-Catalyzed Asymmetric Michael Reaction of <i>tert</i>-Butyl Diphenyliminoacetate and Ethyl Acrylate

Ryoda, Akemi; Yajima, Nana; Haga, Toyokazu; Kumamoto, Takuya; Nakanishi, Waka; Kawahata, Masatoshi; Yamaguchi, Kentaro; Ishikawa, Tsutomu

doi:10.1021/jo701923z

Cited by 61 publications

(21 citation statements)

References 21 publications

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“…It is theoretically possible to introduce five chiral centers in the guanidine system. We found that modified guanidines prepared using our original methods [4][5][6] were effective not only in catalytic [7][8][9][10][11][12][13] but also in stoichiometric asymmetric syntheses. 14,15) The concept of modified guanidines as chiral auxiliaries in asymmetric synthesis is illustrated in Chart 2, [16][17][18] in which reactive, but resonance-stabilized, guanidinium salts 5 could be produced from guanidines 4 by quarternarization with a reagent (A-B).…”

Section: Modified Guanidines As Chiral Auxiliaries (Functionality As mentioning

confidence: 99%

“…7,11) A 1,3-disubstituted (4S,5S)-diarylimidazolidine skeleton 23 with an (R)-1-(2-hydroxymethyl)-2-phenylethylimino moiety at the 2 position (or the enantiomer), which can be prepared using method I, was found to be the most effective catalyst in these reactions, in which an (R)-excess adduct 24 was obtained. Treatment with ethyl acrylate (22a) as a vinyl compound in the presence of catalyst 23a [designated as "(ϩ)-Chiba-G"] smoothly afforded the adduct 24a (97% ee in 85% yield) when the reaction was carried out without solvent (for 3 d), whereas a less effective reaction (79% ee in 15% yield) was observed in tetrahydrofuran (THF) solution (for 7 d).…”

Section: )mentioning

confidence: 99%

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Guanidine Chemistry

Ishikawa

2010

Chem. Pharm. Bull.

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Guanidines are categorized as strong organobases; however, their catalytic utility in organic synthesis has not been discussed thoroughly. The author's group has extensively and systematically studied their potential ability focusing on: 1) modified guanidines as chiral auxiliaries; 2) guanidinium ylides for aziridine formation; 3) the affinity of bisguanidine for proton and metal salts; and 4) the potential chirality of bisguanidine. Under the first topic, a variety of chiral guanidines was designed by the introduction of chirality on the three guanidinyl nitrogens, and the modified guanidines prepared using our original methods were found to be effective not only in catalytic but also in stoichiometric asymmetric syntheses. Under the second topic, the reaction of guanidinium salts carrying a glycinate function with aromatic or unsaturated aldehydes under basic conditions unexpectedly afforded aziridine-2-carboxylates, which were available as useful building blocks in organic synthesis due to their convertibility to functionalized amino acid derivatives in the ring-opening reaction, together with urea compounds recyclable to the starting guanidinium salts. The introduction of a chiral template to the guanidinium salt allowed us to expand the cyclic aziridination reaction to an asymmetric version. Under the third topic, effective complexabilty of bisguanidines with either proton or metal ions in water was observed, suggesting their possible application to the removal of toxic substances from polluted water and recovery of rare elements as material sources. Under the final topic, monomethylation or monoethylation of bisguanidine afforded a chiral product via asymmetric crystallization, indicating that bisguanidines have a potential chiral character due to the plane asymmetry.

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Section: Modified Guanidines As Chiral Auxiliaries (Functionality As mentioning

confidence: 99%

Section: )mentioning

confidence: 99%

Guanidine Chemistry

Ishikawa

2010

Chem. Pharm. Bull.

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“…27 On the other hand, the synthesis of biologically active imidazolines, such as clonidine and indanazoline has been developed by Cussac et al through the condensation between primary amines and imidazolidin-2-ones or 2-methylsulfanyldihydroimidazoles. [28][29][30][31] Other procedures involve the condensation of amines with dihydroimidazol-3-ium-2-sulfonate 32 or with protected imidazolidine-2-thione, though the last procedure requires the use of mercury (II) chloride. 9 As part of our program to develop new procedures for the synthesis of heterocyclic systems, [33][34][35] we investigated several carbon-nitrogen bond forming reactions directed to the synthesis of 2-aminoimidazole derivatives.…”

Section: Figurementioning

confidence: 99%

C-N bond forming reactions in the synthesis of substituted 2-aminoimidazole derivatives

Gómez-SanJuan¹,

Botija²,

Méndez³

et al. 2013

Arkivoc

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Carbon-nitrogen bond forming reactions oriented to the synthesis of 2-amino-imidazolidines and imidazoles have been investigated. The C-2 amination of imidazolidinones, via the corresponding 2-chlorodihydroimidazoles, led to 2-benzylaminodihydroimidazole or bis(dihydroimidazole)amino derivatives by choosing the adequate experimental conditions. On the other hand, the use of N-acyl-2-methylsulfanyldihydroimidazoles allowed carrying out the reactions with aromatic amines, such as p-anisidine. Finally, palladium catalyzed BuchwaldHartwig amination was the method of choice for C-N coupling between 2-haloimidazoles and aromatic amines in the synthesis of the corresponding imidazoles.

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“…For example, we managed to prepare a single crystal of the complex salt of the l-isomer of 1,2-bis(2-methylphenyl)ethylene-1,2-diamine, but not the d-isomer, using 9-(d)-camphorsulfonic acid after several trials of salt formation using tartaric acid, ammonium hexafluorophosphate, or hydrochloric acid. 19) For this purpose, advanced Marfey's method is more suitable because it has the following advantages: 1) Operations are easy; 2) Desired peaks can be definitely detected by mass spectrometry; 3) The 9A-FDLA method is e#ec-tive for identification of the isomers; and 4) The absolute configuration can be definitely determined by the elution order.…”

Section: Elution Behavior Of 12-diphenylethylene-12-diamine Derivatmentioning

confidence: 99%

Optical Resolution of 1,2-Diamino Compounds Using Advanced Marfey's Method

Nozawa

Harada

Ryoda

et al. 2009

J. Mass Spectrom. Soc. Jpn.

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Advanced Marfey's method was successfully applied to the optical resolution of 1,2-diaminoethane compounds. The elution behavior of 1,2-diphenylethylene-1,2-diamine and 1,2-bis(2-methylphenyl)ethylene-1,2-diamine derivatized with A-and 9-FDLA was carefully investigated and the following regularity was found: 1) The (S,S)-isomers are eluted prior to the (R,R)-isomer; 2) The (R,R)-and meso-isomers are closely eluted; 3) There is no di#erence between the retention time of both the A-and 9-derivatives of the meso-isomer; 4) This regularity is fundamentally consistent with that of diamino acids such as diaminopimelic acid and diaminosuccinic acid. Finally, it was confirmed that this method along with the 9A-FDLA method could be applicable for the determination of the absolute configuration of 1,2-diaminoethane compounds because the method can definitely determine it by the elution order.

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Optical Resolution of (±)-1,2-Bis(2-methylphenyl)ethylene-1,2-diamine as a Chiral Framework for 2-Iminoimidazolidine with 2-Methylphenyl Pendant and the Guanidine-Catalyzed Asymmetric Michael Reaction of tert-Butyl Diphenyliminoacetate and Ethyl Acrylate

Cited by 61 publications

References 21 publications

Guanidine Chemistry

Guanidine Chemistry

C-N bond forming reactions in the synthesis of substituted 2-aminoimidazole derivatives

Optical Resolution of 1,2-Diamino Compounds Using Advanced Marfey's Method

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