Amine and alkene

Vinylamines (enamines) are reduced by alane, mono- and dichloroalane to saturated amines, and hydrogenolyzed to amines and alkenes [710]. Reduction is favored by dichloroalane while hydrogenolysis is favored by alane. Alane, chloroalane and dichloroalane gave the following results with -N-pyrrolidinylcyclohexene V-pyrrolidinylcyclohexane in 13, 15 and 22% yield, and pyrrolidine and cyclohexene in 80, 75 and 75% yields, respectively [710]. Saturated amines were also obtained by treatment of enamines with sodium borohydride [711], with sodium cyanoborohydride [103, 712] (Procedure 22, p. 210) and by heating for 1-2 hours at 50-70° with 87% or 9S% formic acid (yields 37-89%) [320]. 

Ammonium ylides possessing a P-hydrogen often undergo an elimination reaction to provide the corresponding amine and alkene.55,57-60 For... 

Sc(OTf)3-catalyzed three-component coupling reactions of aldehydes, amines, and dienes have been examined. In the presence of 10 mol % Sc(OTf)3 and magnesium sulfate, benzaldehyde was treated with aniline and Danishefsky s diene. The desired three-component reaction proceeded smoothly to afford the corresponding tetrahydropyridine derivative in 83 % yield (Eq. 9) [24b]. Under the same reaetion conditions, cyclopentadiene was used instead of Danishefsky s diene to afford the corresponding tetrahydroquinoline derivative (Eq. 10). Different combinations of aldehydes, amines, and alkenes are possible in these reactions, and afford diverse tetrahydroquinoline derivatives in high yields. 

Bearing in mind the usefulness and efficiency of one-pot procedures, three-component coupling reactions between aldehydes, amines, and alkenes via imine formation and imino Diels-Alder reactions were examined by using Ln(OTf )3 as a catalyst. 

Phosphine, Amines and Alkenes as Factors Affecting the Rate of the Oxidative Addition. Amatore, Jutand et al. [29] have established that excess PPhs slows down the oxidative addition by formation of the nonreactive Pd°(PPh3)3(OAc)", thereby decreasing the concentration of the reactive Pd°(PPh3)2(OAc) by equilibrium with Pd°(PPh3)3(OAc) . 

In this chapter, we study two characteristic reactions of haloalkanes nucleophilic substitution and /3-elimination. Haloalkanes are useful molecules because they can be converted to alcohols, ethers, thiols, amines, and alkenes and are thus versatile molecules. Indeed, haloalkanes are often used as starting materials for the synthesis of many useful compounds encountered in medicine, food chemistry, and agriculture (to name a few). 

Late transition metals are particularly useful for enantioselective transformations with protected amines and in some cases arylamines however, simple alkylamines have rarely been addressed using these metal centers. Considering the mechanistic profiles for these reactions and the competitive coordination of amine and alkene with these systems, it would seem that late transition metals are preferred for less nucleophilic amines, while early transition metals and rare earth elements will be preferred for unprotected amines. As such, the development of hydroamination catalysts from different regions of the periodic table can result in complementary synthetic solutions. 

Amines and Alkenes as Factors Affecting the Rates of Both the Oxidative Addition and Carbopalladation The base (NEt ) plays a multiple role. It stabilizes Pd (PPh3)2(OAc) versus its decomposition to Pd"(PPh3)2 by protons and consequently slows down the oxidative addition (Scheme 19.7) [7c, 1, p]. The base accelerates the overall carbopalladation by shifting the equilibrium toward PhPd(OAc)L2 upon quenching the proton (Scheme 19.9) [71]. It favors the recycling of the Pd complex from the hydrido-Pd . The formation of HPd PPhj) was proposed by Heck (Scheme 19.2). In DMF, the cationic [HPd(PPh3)2S] must be formed with acetate as the counter anion (Amatore/Jutand [7m]). 

HRu(CO)(PCy3)2Cl for the preparation of organoboranes from vinylsubstituted boronates and olefins, for the stereoselective synthesis of carbazoles, for the intermolecular coupling of cyclic amines and alkenes. ... 

Formation of C(2)-Substituted Imines from Cyclic Secondary Amines and Alkenes... 

An air-stable, well-defined (NHC)-Ni complex is another effective 3d-metal catalyst for the mild anaerobic catalytic oxidation of secondary alcohols with such functionahties as ether, tertiary amine, and alkene, using nonanhydrous, -degassed 2,4-dichlorotoluene as both oxidant and sol-... 

Whilst there are several examples of late transition-metal stabilised nitrenes in the literature (see below), very few experimental studies are available for copper-nitrene intermediates. These are proposed as important intermediates in copper-catal3 ed alkane amination and alkene aziridination reactions, therefore identification and characterisation is critical for providing new mechanistic insights. Ray et recently... 

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