Diamines from alkenes

There is one direct method of preparing primary diamines from alkenes, in which the alkene is treated with nitric oxide and a cobalt complex, and the intermediate worked up reductively. The two-stage reduction gives better stereoselectivity (Scheme 38). Typical yields from alkenes listed and cisitrans se-lectivities (expected product first) are cyclopentene, 70%, 70 30 rronr-3-hexene, 61%, 90 10 cis-3-hexene, 43%, 66 34 cyclohexene, 47%, 68 32 rra w-l-phenylpropene, 90%, 85 15 cis-l-phe-nylpropene, 74%, 72 28. An alternative oxidative work-up with iodhne gives, at least from the norbor-nene a uct, a dioxime. 

Jung, S. and Kohn, H. (1984) A new reductive procedure for the preparation of vicinal diamines and monoamines. Tetrahedron Letters, 25, 399 02 Jung, S.H. and Kohn, H. (1985) Stereoselective synthesis of vicinal diamines from alkenes and cyanamide. Journal of the American Chemical Society, 107, 2931-2943. 

Diamination of alkenes can also be achieved intramolecularly through the nickel-catalyzed oxidation reaction, affording a wide-range of different cyclic sulfamides <07AG(E)7125>. The cyclization of sulfamide 223 proceeds in the presence of NiCU or Ni(acac)2 (10 mol%) and PhI(OAc)2 with complete selectivity, and no products other than cyclic sulfamides are observed. An initial involvement of aminometalation generates a cyclic intermediate 224. The subsequent oxidative C-N bond formation, presumably via a Ni(III) intermediate from oxidation with PhI(OAc)2, yields the bicyclic sulfamide 225. The reaction scope is well extended to the formation of spiro-cyclic sulfamides, tricyclic sulfamides and chiral substrates... 

The paUadium-promoted vicinal diamination of alkenes can be achieved according to Scheme 39 the example chosen illustrates how the mechanism and stereochonistry were determined. The independent synthesis of (36) from a qualemized aziridine is also notewordiy. Yields are 60-87% from ter-... 

The palladium-ptomoted diamination of alkenes has been modified to yield Ci5-l,4-diamino-2-enes from dienes (Scheme 92). ... 

Benzodithiolethione with diamines gives cyclic amidines (90) in which two sulfur atoms are lost.145 The reaction of (V,(V -dialkyl-l,2-diamino-ethanes with 1,2-benzodithiolethione gives products 91146 which are nitrogen analogs of those obtained from alkenes (see Section III,G). 

Scheme 4.10 Cyclic ureas from intramolecular diamination of alkenes, n = 1, 2.

The reaction has recently been developed further by use of the milder reagents PhIO and PhI(OAc)2, respectively, within the iodine(III)-mediated intramolecular pyrrolidine formation from alkenes. For example, the combined use of iodoso-benzene and trimethylsilyl triflate generates reaction conditions that enable an efficient aminooxygenation of urea precursors 61. Because of the acidic reaction conditions, the final carbon-heteroatom bond formation cannot proceed toward diamination, and aminooxygenation products 62 are obtained selectively. The free aminoalcohols are conveniently obtained by acidic cleavage of the cyclic carbamate [51]. 

Several catalysts that can effect enantioselective epoxidation of unfunctionalized alkenes have been developed, most notably manganese complexes of diimines derived from salicylaldehyde and chiral diamines (salens).62... 

In summary, the reaction of osmium tetroxide with alkenes is a reliable and selective transformation. Chiral diamines and cinchona alkakoid are most frequently used as chiral auxiliaries. Complexes derived from osmium tetroxide with diamines do not undergo catalytic turnover, whereas dihydroquinidine and dihydroquinine derivatives have been found to be very effective catalysts for the oxidation of a variety of alkenes. OsC>4 can be used catalytically in the presence of a secondary oxygen donor (e.g., H202, TBHP, A -methylmorpholine-/V-oxide, sodium periodate, 02, sodium hypochlorite, potassium ferricyanide). Furthermore, a remarkable rate enhancement occurs with the addition of a nucleophilic ligand such as pyridine or a tertiary amine. Table 4-11 lists the preferred chiral ligands for the dihydroxylation of a variety of olefins.61 Table 4-12 lists the recommended ligands for each class of olefins. 

The dimerization of functional alkenes such as acrylates and acrylonitrile represents an attractive route to obtain bifunctional compounds such as dicarboxylates and diamine, respectively. The head-to-tail dimerizahon of acrylates and vinyl ketones was catalyzed by an iridium hydride complex generated in situ from [IrCl(cod)]2 and alcohols in the presence of P(OMe)3 and Na2C03 [26]. The reaction of butyl acrylate 51 in the presence of [IrCl(cod)]2 in 1-butanol led to a head-to-tail dimer, 2-methyl-2-pentenedioic acid dibutyl ester (53%), along with butyl propionate (35%) which is formed by hydrogen transfer from 1-butanol. In order to avoid... 

Jacobsen epoxidation turned out to be the best large-scale method for preparing the cis-amino-indanol for the synthesis of Crixivan, This process is very much the cornerstone of the whole synthesis. During the development of the first laboratory route into a route usable on a very large scale, many methods were tried and the final choice fell on this relatively new type of asymmetric epoxidation. The Sharpless asymmetric epoxidation works only for allylic alcohols (Chapter 45) and so is no good here. The Sharpless asymmetric dihydroxylation works less well on ris-alkenes than on trans-alkenes, The Jacobsen epoxidation works best on cis-alkenes. The catalyst is the Mn(III) complex easily made from a chiral diamine and an aromatic salicylaldehyde (a 2-hydroxybenzaldehyde). 

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