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Photolysis of thioureido derivatives of cymantrene in solution and solvent-free affords stable six-membered dicarbonyl chelates due to coordination of sulfur of the C═S group to manganese. The proc...

1N- and 2N-cymantrenylalkylsubstituted 1,2,3-triazoles were for the first time synthesized. It was found that irradiation by a mercury lamp light with λ = 365 nm of cymantrenylalkyl-1,2,3-triazoles 3, 5–8 gives stable dicarbonyl chelates 4, 9–12. In a closed system without CO removal, intermolecular photochromic systems between tricarbonyl and dicarbonyl complexes were formed; half-conversion time for the dark reaction was more than 10 h. The effect of a substituent position in dicarbonyl chelates 4, 9–12 on the parameters of their spectra, coordination ability of the N atom and chemical stability was studied. It was found that coordination ability of the nitrogen atoms markedly depends on steric hindrances, which are significantly different in 1N- and 2N-substituted triazoles.

The synthesis of new quinazoline derivatives with 2,3- and 4-positioned cymantrenyl fragment is described. Alkylation of 2-substituted quinazolin-4-ones with cymantrenylalkyl bromides on using K2CO3, potassium tert-butoxide, and sodium hydride as bases has been studied. It is established for the first time that condensation of 2-methylquinazolin-4-ones with aldehydes can cause elimination of the substituent at the nitrogen atom in position 3. The new cymantrene derivatives possess fluorescence properties.

The synthesis of four new 1,2,3-triazole derivatives and seven 1,2,3-triazolium salts that contain an organometallic group (i.e., cymantrenyl and ferrocenyl) at either the N-1, N-2, or N-3 position was realized. The alkylation of organometallic and organic triazole derivatives was investigated, and as a result of these studies, it was found that the presence of a good leaving group at the heterocyclic nitrogen atom led to transalkylation and subsequent migration of the N-1 substituent to the N-2 position of the triazole moiety. The nucleophilicity of the counterion of the triazolium salt influenced the transalkylation and isomerization processes, which suggests that the elimination of the N-substituent most likely occurs though a concerted mechanism with nucleophilic assistance from the counterion. Thus, a new approach to the synthesis of 2,4-disubstituted 1,2,3-triazoles has been developed.

Photochemical properties of a series of bifunctional monosubstituted derivatives of cymantrene containing a C-, N-, or O-bound π-allyl group, along with n-donating carbamate, amide, or pyridine fragments were investigated. The results obtained demonstrate that the nature and thermodynamic stability of the cyclopentadienylmanganese dicarbonyl chelates derived from bifunctional monosubstituted cymantrene derivatives depend substantially on both the nature of the functional groups and on their position in the substituent at the Cp ring. Thus, for the six-membered chelates, the thermodynamic stability increases in the series carbamates < amides < pyridines < olefins. Some of the dicarbonyl chelates studied form reversible photochromic systems due to linkage isomerization between different donating groups of the bifunctional substituent and the manganese atom with a wide range of times of thermal isomerization.

Procedures were developed for preparation of optically active dendrones and dendrimers with terminal 1,2-hydroxylimino, 1,2-hydroxylamino and oxazolidinyl groups containing ether bonds in the branches and ester bonds in the backbone of the macromolecule. The compounds described may serve as chiral ligands for asymmetric metallocomplex catclysis.

Series of chiral monodentate phosphite-type ligands has been evaluated in the rhodium-catalyzed asymmetric hydrogenation of dimethyl itaconate in both dichloromethane and supercritical CO 2 . High reactivities (100% conversion in 1.5–3 h) and enantioselectivities (up to 90%) were obtained in the hydrogenation in scCO 2 .

Optically active phosphite-type ligands with planar chirality have been synthesized for the first time. The new cymantrene-based P,N-iminodiamidophosphites demonstrated high enantioselectivity in the Pd-catalyzed allylic substitution of 1,3-diphenylallyl acetate with dimethyl malonate (up to 94% ee), pyrrolidine (up to 78% ee) and sodium para-toluene sulfinate (up to 84% ee).

A series of chiral phosphite-type ligands has been evaluated in the iridium-catalyzed asymmetric hydrogenation of acyclic arylimines in supercritical CO 2 . High reactivities (100% conversion in 50–120 min) and enantioselectivities (up to 95%) were obtained.

A new preparative method for the synthesis of Schiff bases by the solid-state interaction of crystalline organic and organometallic aldehydes and amines is suggested. The possibility of direct synthesis of aldimines in the solid state from amine salts without isolation of the free amines is demonstrated.

A number of organic and organometallic aldehydes have been converted into optically active oxazolidines by solid-state interaction with (-)-ephedrine and (+)-pseudoephedrine. The stereoselectivity of the solid-state reaction is compared with that in boiling ethanol solution.

The reaction of dicymantrenyl ketone with the Grignard reagent 2,4,6-Me3C6H2MgBr in THF occurs as the insertion of the mesityl substituent in the α-position of one of the cyclopentadienyl rings to give (2-mesitylcymantrenyl) cymantrenyl ketone (4), rather than as addition at the C=O group. Reduction of4 by NaBH4 in a THF-EtOH mixture affords (2-mesitylcymantrenyl)cymantrenylmethanol (5). Ionic hydrogenation of5 with the HSiEt3/CF3COOH system gives (2-mesitylcymantrenyl)cymantrenylmethane (7). The structure of alcohol5 has been established by X-ray diffraction analysis.

A series of chiral phosphite-type ligands has been evaluated in the iridium-catalyzed asymmetric hydrogenation of acyclic arylimines in supercritical CO 2 . High reactivities (100% conversion in 50–120 min) and enantioselectivities (up to 95%) were obtained.

The solid-state interaction of the three-component mixtures (ferrocenylcarbaldehyde: methyl ester of amino acid hydrochloride: K2CO3) afforded new optically active Schiff bases.

Organometallic derivatives of 2,3-dihydroperimidine were obtained by the solid state interaction of ferrocene-, cymantrene-, and ruthenocenecarbaldehydes with 1,8-naphthylenediamine.

On the basis of IR spectra and molecular mechanics calculations, the conformations stabilized by hydrogen bonding in α-carbinol derivatives of cyclopentadienyltricarbonyl manganese and rhenium have been determined. Intramolecular H-bonds with Mn and Re atoms are found in the tertiary carbinols. Relative stability of the OH ⋯ M hydrogen bonds increases in accordance with metal basicity (Mn

The solid-state interaction of the three-component mixtures (ferrocenylcarbaldehyde: methyl ester of amino acid hydrochloride: K2CO3) afforded new optically active Schiff bases.

Novel chiral monodentate phosphite ligands bearing cymantrene fragment have been prepared. Phosphite 4 with PPh3, instead of CO-ligand, in cymantrene moiety provided higher enantioselectivity than its unsubstituted analogue 3 in hydrogenation of (Z)-methyl-2-acetamido-3-phenylacrylate.

The solid-state reactions of crystalline ferrocenyl- and ruthenocenylaldehydes with optically active primary β-hydroxyamines were studied at ∼20 °C. The yield of the products increases substantially in the presence of K2CO3. The tautomeric equilibrium between imines and diastereomeric oxazolidines with the predominant formation of one of them is established in solutions of the products in CDCl3.

With the aim of modifying solid dendrite structures, the solid-state reactions of (S)-(−)-(1-trimethylammonio)ethylferrocene iodide with substituted phenols were studied.

Replacement of one CO ligand in the enantiomeric 2-methylcymantrenecarboxylic acid ester for a radical ligand PhS results in the preparation of stable and optically active odd-electron complex CH3C5H3COOCH3Mn(CO)2SPh]. fully characterized by electron spin resonance, mass spectroscopy, UV-visible spectroscopy, IR spectroscopy and circular dishroism spectroscopy. This is the first example of an optically active organometallic free radical.

Organometallic derivatives of 2,3-dihydroperimidine were obtained by the solid state interaction of ferrocene-, cymantrene-, and ruthenocenecarbaldehydes with 1,8-naphthylenediamine.

Resolution of α-aminoethylcymantrene (I) to its enantiomers has been effected for the first time by means of (+)- d -tartaric acid. The molecular structure and absolute configuration of (+)-( R) -α-( N -acetylamino)ethylcymantrene prepared from ()-I have been established by an X-ray analysis. On the basis of chemical and chiroptical correlation methods the R -configuration of the chiral centre is also assigned to ()-I, (+)-α-( N,N -dimethylamino)ethylcymantrene, (+)-II, and (+)-α-( N , N , N -trimethylammonium)ethylcymantrene iodide, (+)-III. ORD and CD curves of the prepared optically active compounds have been studied

The effect of the planar and central chirality of 1,2(α-(N,N-dimethylamino)alkyl)formylcymantrene on the chromatographic properties of diastereomeric chelates of Cu2+ with Schiff bases from dipeptides and the aminoalklylformylcymantrenes, 1-(N,N-dimethylaminomethyl)-2-formylcymantrene (I) and 1,2(α-(N,N-dimethylamino)ethyl)formylcymantrene (III), has been studied by liquid chromatography. The method described has been shown to allow the separation of diastereomeric chelates of the cymantrene derivative with differing metallocene chirality. The central chirality in III does not make any noticeable contribution to the chromatographic separation of chelates. Acid hydrolysis of chelates after the chromatographic separation gives enantiomers of I and III. The formation of chelates proceeds stereospecifically. 1,3-Isomers of aminoaldehydes of I and III do not form chelates with Cu2+ ion and dipeptides. The synthesis of chelates using L -Ala- L -Ala in the presence of oxygen is accompanied by epimerization of the N-terminal aminoacid moiety of the dipeptide. p]The resulting diastereomeric chelates and optical isomers of aminoaldehydes of cymantrene I and II isolated from them are characterized by elemental analysis data, ORD, PMR, UV and IR spectra.

The molecular structure and the absolute configuration of (−) 578 -1-[α-( N,N -dimethylamino)ethyl]-2-formylcymantrene have been established by the X-ray method. These data were used for the direct determination of the orientation and stereochemistry of the preferable attack of n-BuLi on metallation of [α-( N,N -dimethylamino)ethyl]cymantrene. CD and UV spectra of (−)-( S )-1-[( R -α-( N,N -dimethylamino)ethyl]-2-formylcymantrene (planar and central chirality) and (−)-( S )-1- N,N -dimethylaminomethyl-2-formylcymantrene, I (only planar chirality) and related compounds have been studied, a change in both the sign and the intensity of Cotton effects is observed between solutions of I and II in aprotic solvents and solutions in 0.1 N HCl and quaternary salts of these compounds. The data obtained indicate that the optical characteristics of aminoaldehydes of cymantrene are determined by the conformation of these molecules but not by their absolute configuration.

The mass spectrometry behaviour of dimethylaminomethyl- and α-(dimethylamino)ethyl derivatives of cymantrene and ferrocene, their iodine methylates as well as of the deutero analogues of these compounds has been studied. It has been shown that mass spectrometry can be successfully employed for the quantitative determination of the total deuterium content in aminoalkyl derivatives of cymantrene and ferrocene, the distribution of the label between the dimethylaminoalkyl group and the metallocenyl fragment and in case of the dimethylaminomethylferrocene also between the substituted and unsubstituted cyclopentadienyl rings. The data on the distribution of the isotopic label were used to ascertain the mechanism of fragmentation of the dimethylaminomethylferrocene under electron impact.

Dimethylaminomethyl- and hydroxymethyl-cymantrenes, when treated with n-butyllithium, are selectively metallated in the 2(5) position of the Cp ring and are converted into 1,2-disubstituted derivatives of cymantrene by subsequent treatment with electrophilic reagents. Similar reactions in the case of diphenylphosphinocymantrene result in a selective preparation of 1,3-disubstituted derivatives. The metallation orientation is established by chemical methods and NMR-LIS (lanthanide-induced shift) techniques. A full assignment of signals in the PMR and 13 C NMR spectra of the studied monosubstituted cymantrene derivatives has been effected.

13C NMR spectra of some α-cymantrenylcarbenium ions and corresponding carbinols are reported. The data obtained are compared with the characteristics of the 13C NMR spectra of ferrocenyl-, phenyl- and cyclopropyl-carbenium ions. The mechanism of the carbenium centre stabilization by the adjacent metallocenyl radical is discussed.

The optical isomers of 2-formyl( N , N -dimethylaminomethyl)cymantrene (I) can be separated by liquid chromatography of Cu 2+ chelates of the Schiff bases formed from I and a number of dipeptides, in those cases where no racimization of the amino acid residues in the initial dipeptide occurs. Hydrolysis of the chelates gives optically pure enantiomers of I. Under the conditions of the preparation of the chelate from L-Ala-L-Ala (NH 2 C(CH 3 )HCONHC(CH 3 )HCOOH) slow epimerization of the dipeptide into D-Ala-L-Ala takes place. Formation of Cu 2+ chelates of the Schiff bases from L-Ala-L-Ala, D-Ala-L-Ala and L-AlaGly (NH 2 C(CH 3 )HCONHCH 2 COOH) with (+) - and (-) -I proceeds stereospecifically.

Substitution of the hydrogen atoms of the cyclopentadienyl ring of ( N , N -dimethylaminomethyl)cymantrene by deuterium changes the direction of orientation of metalation of this amine.

PMR and UV spectra, in acid media, of some α-cymantrenylcarbenium ions are reported. The data obtained proves that the nature of the stabilisation of the positive charge is common to both cymantrenylcarbenium and ferrocenylcarbenium ions. Also reported are the values of p K R + for the equilibrium (CO) 3 MnC 5 H 4 CR(R′)(OH) ⇌ (CO) 3 MnC 5 H 4 CR(R′), (R = H, CH 3 , C 6 H 5 ; R′ = C 2 H 5 , C 6 H 5 , p -C 6 H 4 OCH 3 )

1-(N,N-Dimethylaminomethyl)-2-formylcymantrene (AFCMT) has been resolved into enantiomers through an intermediate formation of diastereomeric complexes with ( S )-Ala-( S )-Ala, ( S )-Ala-Gly and Gly-( S )-Ala. By the X-ray anomalous dispersion method the absolute configuration of its enantiomers has been determined: (-) 436 AFCMT-( S ), (+) 436 AFCMT-( R ). Alkylation of enantiomeric complexes ( R )-and ( S )-AFCMT-(GlyGly) Cu(II) with acetaldehyde gives, respectively, ( R )-and ( S )-Thr with an asymmetric yield of 92–98% and ( R )- and ( S )-allo-Thr with an asymmetric yield of 95–100%, only the N-terminal glycine being alkylated. The AFCMT enantiomers were also employed for retroracemisation of ( R,S )-Ala-( R,S )-Nva; in this case an excess of ( S )-Ala and ( R )-Nva is obtained for ( S )-AFCMT. ( R )- and ( S )-AFCMT are not liable to racemisation in the course of the threonine synthesis and retroracemisation of depeptides and can be repeatedly employed for these transformations.

The results of the study of the chiroptical properties (CD, ORD and [α]), of fourteen optically active monosubstituted cymantrene derivatives with a chiral center directly attached to the Cp ring are summarized for the first time. It has been found that the ( R )-enantiomers of these compounds exhibit a negative Cotton effect for the “metallocenyl” transition in CD spectra within the range 310–360 nm independent on the nature of the substituent and the solvent.

CONTENTS I. Introduction 105 II. Methods of synthesis of aziridine 105 III. Structure and properties 108 IV. Reactions of aziridine and its derivatives 110 V. Identification and quantitative determination of aziridine derivatives 115 VI. Action on living organisms 116 VII. Main technical uses 116

The action of triethylsilane and excess trifluoracetic acid upon cyclic and acyclic olefines at room temperature results in a selective hydrogenation when the olefins has two substituents at the ethylene carbon. Excess of trifluoroacetic acid is essential for the reaction. Under more drastic conditions (heating in ampoules at 140° or using a large excess of trifluoroacetic acid) cyclic and acyclic olefins with unbranched structure and inner double bond are capable of undergoing hydrogenation although this is sometimes accompanied by isomerization. In addition to triethylsilane, cycloheptatriene and saturated branched hydrocarbons have been used as hydride-ion donors. It has been found that the action of trifluoroacetic acid and triethylsilane on ketones yields trifluoroacetates of corresponding alcohols. If at least one of the ketone radicals is phenyl, hydrogenation is more likely to result in the formation of a hydrocarbon. Benzophenone and acetophenone give after 15–20 hr at 50–60° diphenylmethane (90%) and ethylbenzene (70%) respectively.

1. Ionic hydrogenation is a convenient method for the synthesis of 2-benzyl-substituted 1,3-indandiones from readily available compounds. 2. The carbonyl groups of the ring of 1,3-indandiones do not react with the triethylsilane — trifluoroacetic acid hydrogenating couple.

1. The ionic hydrogenation of acyl derivatives of cyclopentadienylmanganese tricarbonyl was studied. 2. The ketone group is converted to an alcohol group or a methylene group, depending on the structure of the starting carbonyl compound. 3. The cyclopentadienylmanganese tricarbonyl radical stabilizes the neighboring electron-deficient center more strongly than the phenyl ring.