Phenyl aziridines

AZIR1DINAMINE, ( ) 2-phenyl- [Aziridine, 1-armno 2 phenyl-], 55, 55, 114 1-AZIRID1NAMINE, ( ) 2 phenyl, mono... 

It is possible to prepare aziridines, which are synthetically important molecules, directly from the corresponding epoxide. Reaction of Ph3P=NPh with an epoxide in the presence of ZnCl2 gives the N-phenyl aziridine. ... 

In the reaction of fused aziridines with alkene dipolarophiles, the opportunity for stereoselectivity as well as facial selectivity arises since exo- or entfo-isomers can be formed (Scheme 10). In practice, maleic anhydride 6, A-methyl maleimide and JV-phenyl maleimide each reacted exo-stereoselectively with TV-benzyl aziridine 69 to form adducts of type 71 (Scheme 10b), the stereochemistries of which were confirmed by NOE measurement between Hb and He. Similar reaction of the Y-phenyl aziridine 67 with N-Ph maleimide gave a 1 1 mixture of endo-adduct 72 and exo-adduct 73 (Scheme 10c). Adducts 68, 71-73 all exhibited a low-field methano-bridge proton (Ha) in the range 5 3.06-3.60 confirming the syn-facial stereochemistry of the two bridges. 

Ahnlich verhalt es sich bei der fluorierenden Ringoffnung anderer, substituierter Aziridine, wobei 2-Phenyl-aziridine bevorzugt bis ausschlieBlich am C-2, also dem benzylischen C-Atom, fluoriert werden z. B. ... 

The iodine-catalyzed reaction of aziridines with carbon dioxide leads to 2-oxazolidinones (251). Because carbon dioxide effectively polymerizes ethyleneimine, only low yields are obtained when unsubstituted ethyleneimine reacts with C02. However, direct insertion of carbon dioxide [124-58-9] into aziridines can be accomplished, with better yields, by ethoxycarbonylation of aziridines with subsequent elimination of ethylene under flash vacuum conditions (252). 1- Phenyl aziridine [696-18-4] can react with C02 under antimony [7440-56-0] catalysis to give AI-phenyl-2-oxazolidinone in good yields (253). At low temperatures and with the exclusion of atmospheric humidity, the reaction of ethyleneimine with carbon dioxide produces the unstable ethyleneiminium salt [51645-58-2] of IV-vinylcarbamic acid (254,255). 

When 1-phenyl aziridine or 1 -(p-tolyl)aziridine is treated with sodium iodide in boiling ethanol-water solution the corresponding disubstituted piperazines are formed (62). In the absence of the salt only polymerization took place. The piperazines are most probably formed by the same mechanism as proposed by Dick. 

Dihydrooxazoles are quite rare they are produced by the thermal rearrangement of C-acylaziridines (equation 161). Both cis- and trans-2-benzoyl-l-cyclohexyl-3-phenyl-aziridine react with diphenylcyclopropenone to yield compound (302 equation 162). ITie... 

Aziridine syntheses. A recent discovery by a Japanese group is that reduction of dibenzylketoxime with lithium aluminum hydride affords cis-2-benzyl-3-phenyl-aziridine (2) in good yield and with only minor overreduction to (3). 

Der EinfluB von Katalysatoren und von Losungsmitteln wurde am Beispiel des 2-Me-thyl-2-phenyl-aziridins naher untersucht6 ... 

Methylamino-(+)-l-phenyl-propan1 20 g (-)-l,2-Dimcthyl-3-phenyl-aziridin werden in 75 ml Athanol gelost und mit 0,3 g Palladium/Kohle (10 /o) in einer 250 ml Schiittelente bei 2071 bar hydriert. Die Wasser-stoff-Aufnahme verlauft anfangs sehr schnell (2 //30 Min.) und ist nach 4 Stdn. beendet Wasserstoff-Ver-brauch 3110 ml (0°, 1 bar). Nach Abfiltrieren des Katalysators wird i. Vak. destilliert Ausbeute 17,9 g (89% d.Th.) Kp,2 84° F (Hydrochlorid) 174° (aus Athanol) a = 16,6° (Wasser). 

Aziridine werden, wie bereits oben erwahnt, mit Natrium/fl. Ammoniak je nach Substi-tuenten vor allem am N-Atom zu offenkettigen Aminen oder unter Sticks toff-Ver-lust und C-C-Spaltung zu Alkanen reduziert3. So erhalt man z.B. aus l,2,3 Triphenyl-bzw. 2,3-Diphenyl-l-(4-chlor-phenyl)-aziridin in 66 bzw. 73%iger Ausbeute 1-Anilino-1,2-diphenyl-athan (Kp I68-1700)3 ... 

C,HrXN-N(C,H,)2 N-Amino phenyl-aziridine Girard reagents Tosylhydrazine HN NH Alkyl azides Picryl azide Cyanogen azide Ng, Dicyclohexyl-ammonium azide Guanidinium azides Azidinium salts HNs NH2OH... 

Similar photolysis of either cis- or /ran5-l-ethoxycarbonyl-2,3-di-phenyl-aziridine gives only isomerization and leads to the same isomer mixture... 

Sc(OTf) 3-catalyzed 1,3-dipolar cycloaddition reactions of phenyl aziridines with olefins such as cyclic enol ethers and allyltrimethylsilane also proceeded well [36]. Sc(OTf)3 could also be used as a catalyst for [3 + 2] cycloaddition of aziridines with various nitriles to give the corresponding imidizalines in good to excellent yields under solvent-free conditions (Scheme 12.20) [37]. Although a relatively large amount of Sc (OTf) 3 was used in this reaction, the fast reaction rate, mild conditions and experimental operational ease are the features of this system. 

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