Amination of Allyl Alcohols

Recently, particular ligands have been reported to enable the amination of allyl alcohols without the aid of activators (Scheme 10).13c,13d Ozawa s group found that (7r-allyl)palladium complex 58 bearing. s/>2,2a,2b-hybridized... 

More recently, Hartwig and coworkers reported iridium-catalyzed, asymmetric aminations of allylic alcohols in the presence of Lewis acid activators [103]. The addition of molecular sieves and Nb(OEt)5 or catalytic amounts of BPh3 activated the allylic alcohol sufficiently to allow allylic amination reactions to occur in high yield, branched-to-linear selectivity, and enantioselectivity (Scheme 29). Without the activators, only trace amounts of product were observed. 

Scheme 9.23 Ir-catalyzed asymmetric aminations of allylic alcohols.

The Ru(II) complex (192)-catalysed reductive amination of allylic alcohols RCH=CHCH20H, by various amines R R NH to give R(CH2)3NR R, in toluene was described formic acid and the allylic alcohol act as the hydrogen source. " ... 

The gold-catalysed intramolecular amination of allylic alcohols with alkylamines has provided substituted pyrrolidine and piperidine derivatives with excellent yields and selectivities (up to 99% yield and 96% ee)." The reaction mechanism was found to be consistent with the net syn addition of the amine relative to the departing hydroxyl group (Scheme 6). The synthesis of functionalized carbazoles through gold-catalysed deacylative cycloisomerization of 3-acylindole/ynes has been reported. ... 

A 1 1 1 mixture of AuCl, (f-Bu)2(o-biphenyl)P, and AgSbFg can catalyse the intramolecular amination of allylic alcohols with a suitably located amino group... 

Some nucleophiles other than carbon nucleophiles are allylated. Amines are good nucleophiles. Diethylamine is allylated with allyl alcohol[7]. Allylammes are formed by the reaction of allyl alcohol with ammonia by using dppb as a ligand. Di- and triallylamines are produced commercially from allyl alcohol and ammonia[l74]. 

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... 

The selectivity in the Heck reaction of allylic alcohol 111 is interesting, and the factors that lead to the observed preference for (3-hydride elimination toward nitrogen in this system are unclear, although a combination of steric effects and stereoelectronic factors (i.e., alignment of C-H and C-Pd bonds, nN a c H interactions) is likely involved. Examination of related examples from the literature (Scheme 4.20) reveals no clear trend. Rawal and Michoud examined substrate 115, which lacks the influence of both the amine and hydroxyl substituents and also seems to favor (3-hydride elimination within the six-membered ring over formation of the exocyclic olefin under standard Heck conditions [18a]. However, under... 

One of the rare applications of selenium-substituted allenes was recently reported by Ma et al. [182]. The allenyl selenide 352 undergoes an iodohydroxylation or iodo-amination, depending on the amount of water used, leading to the formation of allyl alcohol 353 and allylacetamide 354 (Scheme 8.97). When the reaction is performed with 12-16 equiv. of water, allyl alcohol 353 is exclusively formed, whereas the use of 1 equiv. of water exclusively provides the amide 354 in 64% yield. 

For Rh(I)/BINAP-catalyzed isomerizations of allylic amines, the mechanistic scheme outlined in Eq. (2) has been proposed. The available data are consistent with the notion that Rh(I)/PF-P(o-Tol)2-catalyzed isomerizations of allylic alcohols follow a related pathway [11]. For example, the only deuterium-containing product of the reaction depicted in Eq. (9) is the l,3-dideuterated aldehyde, which estabhshes that the isomerization involves a clean intramolecular 1,3-migration. The data illustrated in Eqs. (10) and (11) reveal that the catalyst selectively abstracts one of the enantiotopic hydrogens/ deuteriums alpha to the hydroxyl group. 

One of the landmark achievements in the area of enantioselective catalysis has been the development of a large-scale commercial application of the Rh(I)/BINAP-catalyzed asymmetric isomerization of allylic amines to enamines. Unfortunately, methods for the isomerization of other families of olefins have not yet reached a comparable level of sophistication. However, since the early 1990s promising catalyst systems have been described for enantioselective isomerizations of allylic alcohols and aUylic ethers. In view of the utility of catalytic asymmetric olefin isomerization reactions, I have no doubt that the coming years will witness additional exciting progress in the development of highly effective catalysts for these and related substrates. 

Aiming at easier workup conditions, immobilization of several transition metal catalysts, which show activity for the epoxidation of allylic alcohols, on polymer support has been investigated. For example, Suzuki and coworkers incorporated an oxo-vanadium ion into cross-linked polystyrene resins functionalized with iminodiacetic acid or diethylenetri-amine derivatives (Scheme 57), which afforded a heterogeneous catalyst that can promote... 

This procedure illustrates a general method for the preparation of rearranged allylic amines from allylic alcohols.2,3 The method is experimentally simple and has been used to prepare a variety of allylic prim-, sec-, and tert-carbonyl amines as illustrated in Table I. The only limitation encountered so far is a competing ionic elimination reaction which becomes important for tri-chloroacetimidic esters of 3-substituted-2-cyclohexen-l-ols.3 4 The rearrangement is formulated as a concerted [3,3]-sigmatropic rearrangement on the basis of its stereo- and regiospecificity3,5 which are... 

---