Aminocyclopropane moiety

The acid-catalysed rearrangement of N-aryl 2-azabicyclo [3.1.0]hexanes, where the aromatic system is conjugated with an alkene group located at the ortho position relative to the nitrogen atom, gives dihydroquinolines or polycyclic aminocyclobutanes via an iminium intermediate formed by protonation of the aminocyclopropane moiety... 

Cha s group [89] has recently developed a convenient method for the ring opening of tertiary aminocyclopropane tethered with an alkenyl moiety 199. The PET reaction of 199 led to formation of the five-membered bicyclic system 200 through a [3 + 2] annulation reaction in a good yield, as shown in Scheme 8.55. 

Aminocyclopropanes with an aryl or heteroaryl moiety as MAO inhibitors... 

Aminocyclopropanes (1) are typical representatives of the family of donor-substituted cyclopropanes. The combination of an amino moiety with the cyclopropane ring is not only of theoretical interest for possible donor-acceptor interactions, but is also the origin of an easy nucleophilic substitution of a group X in (1) or a ring-opening reaction. Intermediates 2 and 3 represent these two types of reactions according to the sequence 1 - 3 an aminocyclopropane is to be regarded as a homoenamine species. 

The following review covers especially the synthesis of aminocyclopropanes it deals with compounds in which a NR R moiety (R R heteroatom) is directly bonded to the three-membered ring. Cyclopropanes with other nitrogen functional groups are not included. Literature was considered until the end of 1984 the text was supplemented in October 1985. A very short review on aminocyclopropane chemistry appeared in 1974 by Gibson and DePuy Wasserman and coworkers surveyed some aminocyclopropane compounds derived from cyclopropanones. ... 

An interesting, highly selective approach to both diastereomers of some aminocyclopropanes started with diesters of type 63 or 67. Saponification of 63 took place preferentially at the sterically less hindered trans- or exo-position (for references see Table 1). The free acid moiety in 64 could be transformed into an amino compound (66) via the carboxylic azide. Thereby, the ester carboxyl remained unaffected. On the other hand, the ester function of 64 could be converted into the amine (65) via the hydrazide without affecting the acid function (equation 10). Decarboxylation of 64 followed by ester amine... 

Thermolysis of pyrazolines was also used for aminocyclopropane synthesis. The corresponding starting materials were obtained from diazomethane and an alkene bearing a suitable nitrogen functional group, e.g. an amido or azido moiety. 

Aminocyclopropanes bearing a suitable leaving group in the a-position have been extensively used for the synthesis of further aminocyclopropane derivatives. Thereby, an amino, a hydroxy, a methoxy or a trimethylsilyloxy moiety in 375 could be displaced by other substituents leading to 377. Acidic medium or a large excess of the nucleophile (as in solvolysis reactions) or activation of the leaving group (e.g. by quaternization of an amino... 

Interconversion of an imino functional group into an amino moiety by hydrolysis is part of those aminocyclopropane syntheses in which an imino, imidato, thioimidato or amidino... 

Further applications of an azido or an isocyano function as a masked amino moiety in aminocyclopropane synthesis are described in Section II.C.3 (equation 62 and Sections II.B.l.c and II.B.2.a (Scheme 3 and equation 50). 

In general, the behavior of the amino moiety in 1 showed no great differences from that of alkylamines or other cycloalkylamines. Cyclopropylamine (77) (pK = 9.10 ) was found to be somewhat less basic than isopropylamine (pK = 10.67 ) further pK values for 77 and other aminocyclopropane derivatives are reported in Refs 347,483 486. Interactions of 77 with p-fluorophenol , propane-2-thiol , H in the presence of 18 crown-6 or Ag have been investigated. For considerations of the protonation of 77 in the gas phase see Refs 491-493. Different basicity was observed for NR2 groups in the exo and endo-posiiion of a [3.1.0] bicyclic system . 

Opening of the vicinal carbon-carbon bond in aminocyclopropane derivatives was achieved by oxidation with various reagents, e.g. Pb(OAc)4 , NaOCP r-BuOCpi Cu2 /0 Cu/0 0s04/0 K3Fe(CN) Cu or fiv/Oa/sens., anodic oxidation Oxidation with halogenating reagents such as NaOCl or t-BuOCl proceeds via N-chloro compounds (see equation 105), which opened the C(l)-C(2) cyclopropane bond when the cyclopropylamine had one substituent at the iV-atom (e.g. 489- 490 equation 125) or a phenyl moiety in the C(2) position. 

On the other hand the amino moiety in some bi- or polycyclic aminocyclopropanes could be substituted by diazotation without appreciable ring-opening 56.61,110.124,147,152 great steric influence of the diazonium group on the... 

Aminocyclopropane carboxylic acid deaminase, obtained from Pseudomonas bacteria, decomposes 6 to ammonia and 2-ketobutyrate (647)3 i43.733-735 gy using R- and S-2,2-dideuterio-(6) it was shown that the methyl group in 647 has its specific origin in the pro-S methylene moiety of 63 ... 

The cyclopropylamine scaffold is a recurrent moiety in several natural products or drugs [24]. However, its preparation usually requires several steps [25]. Szy-moniak and Bertus have developed an amino version of the Kulinkovich [26] reaction for quicker access to these aminocyclopropanes from nitrile derivatives, Grignard reagents, and titanium isoproxide (Scheme 9.15) [27]. Starting from p- or... 

Zhang HP, Kayeka H, Osada H. Biosynthesis of 1-aminocyclopropane-1-carboxylic acid moiety on cytotrienin A in Streptomyces sp. Tetrahedron Lett. 1998 39 6947-6948. 

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