Dienes amine reagents

Selenium diimides react in a manner similar to SeOa with unsaturated organic compounds. The first report of BuN=Sc=N Bu described its use as an in situ reagent for allylic amination of olefins and acetylenes. Improved procedures for this process (Eq. 10.5) and for the diamination of 1,3-dienes (Eq. 10.6) have been developed using the reagents RN=Se=NR [R = para-toluenesulfonyl (Ts), ort/io-nitrobenzenesulfonyl (Ns)]. ... 

A great advantage of catalyst 24b compared with other chiral Lewis acids is that it tolerates the presence of ester, amine, and thioether functionalities. Dienes substituted at the 1-position by alkyl, aryl, oxygen, nitrogen, or sulfur all participate effectively in the present asymmetric Diels-Alder reaction, giving adducts in over 90% ee. The reaction of l-acetoxy-3-methylbutadiene and acryloyloxazolidinone catalyzed by copper reagent 24b, affords the cycloadduct in 98% ee. The first total synthesis of ewt-J -tetrahydrocannabinol was achieved using the functionalized cycloadduct obtained [23, 33e] (Scheme 1.39). 

Coniine, molecular model of. 28 structure of, 294 Conjugate acid, 49 Conjugate base, 49 Conjugate carbonyl addition reaction, 725-729 amines and, 727 enamines and, 897-898 Gilman reagents and, 728-729 mechanism of, 725-726 Michael reactions and, 894-895 water and. 727 Conjugated diene, 482... 

Silylformylation of 1-alkynes proceeds smoothly even in the presence of a base or a protic reagent. This feature makes it possible to design a cascade-type condensation using the resultant 3-silylalkenals as a component in one-pot operation during the silylformylation. Aza-1,3-dienes 303 are formed with sufficient selectivity by the reaction of 1-alkyne, a hydrosilane, primary amine, and GO under the silylformylation conditions (Equation (52)). ... 

Vinyl substitution occurs with conjugated dienes as well as with alkenes, employing aryl-, vinyl-, methyl-, alkoxycarbonyl- or benzyl-mercury reagents and lithium tetrachloropalladate(II), but the products are usually rr-allylpalladium complexes if the reactions are carried out under mild conditions (equation 8).24,25 The ir-allylic complexes may be decomposed thermally to substituted dienes26 or reacted with nucleophiles to form allylic derivatives of the nucleophile. Secondary amines, for example, react to give tertiary allylic amines in modest yields, along with dienes and reduced dienes (equation 9).25... 

The issue became one of selective reduction of the 1,3 diene moiety, and various conditions for 1,4 hydrogen addition were examined. Unfortunately, all of these failed. For 43, complex, difficult to purify mixtures of various reduction products were generated under various hydrogenation and dissolving metal conditions (Scheme 21).42 The amines 46 and 47 had the additional problem of the readily reducible alkenyl iodide segment. Indeed, exposure to hydride reagents led to quite facile hydrodehalogenation, with products such as 52. Thus, it became... 

Cycloamination of 13-dienes.1 Linear and cyclic 1,3-dienes react with the reagent and primary aryl amines to form 1,4-cycloadducts. 

Over the past ten years, absolute rate data have been reported on the kinetics of several bimolecular silene reactions in solution, including both head-to-tail and head-to-head dimerization the [l,2]-addition reactions of nucleophilic reagents such as water, aliphatic alcohols, alkoxysilanes, carboxylic acids and amines and the ene-addition, [2 + 2]-cycloaddition and/or [4 + 2]-cycloaddition of ketones, aldehydes, esters, alkenes, dienes and oxygen. The normal outcomes of these reactions are summarized in Scheme 1. 

Cyclizations involving sulfenyl chlorides must be designed carefully, since these reagents can also react with alcohols, amines and other nucleophiles. Benzenesulfenyl chloride has been used to cyclize a 1,4-diene. For example, diene (4) cyclizes in good yield to tricyclic heptane product (5). This material was then further elaterated to a cyclosativene precursor (6 equation 4). ... 

---