The propargyl Claisen rearrangement is a known protocol to gain access to functionalized allenes through the [3,3]-sigmatropic transformation of propargyl vinyl ethers. The correct use of appropriate propargyl vinyl ethers as starting materials coupled with suitable reaction conditions can aid in the development of new domino methodologies in which the allenes are valuable intermediates in rout...

A series of 3-allenyl benzo[b]thiophenes were synthesized through a gold(I)-catalyzed domino reaction. The process consists in 5-endo-dig cyclization with C−S bond formation and consecutive S-to-C propargyl migration via [3,3]-sigmatropic Claisen rearrangement. With aryl substituents on both triple bonds the substrate, subsequent intramolecular hydroarylation formed allenyl system led to 3-inde...

γ-Aminobutiric acid (GABA), the major inhibitory neurotransmitter in the central nervous system is activated by the antispastic and muscle relaxant agent, Baclofen, which is a lipophilic derivative of GABA. Because of its biological and pharmacological importance, there are several reports in the literature about the synthesis of baclofen since 1962. In this study baclofen was easily synthesize...

In order to construct the functionalized AB ring system of clifednamide, member of the class of macrocyclic tetramic acid lactams, a synthesis was developed which utilized an Ireland-Claisen rearrangement and an intramolecular Diels-Alder reaction. Starting from di-O-isopropylidene-d-mannitol the allyl carboxylate precursor for the sigmatropic rearrangement was prepared. This rearrangement proc...

Unprecedented stereocontrolled Claisen rearrangement of allylic vinyl ethers has been developed with modified organoaluminum reagents A and B as an example of diastereoselective activation of ethereal substrates. The stereoselective activation of ether moiety is the subject of our current interest. Oxygenophilic organoaluminum reagents are known to exhibit the great tendency to form stable ethe...

A concise synthesis of homocitric acid lactone was developed to accommodate systematic placement of carbon isotopes (specifically (13)C) for detailed studies of this cofactor. This new route uses a chiral allylic alcohol, available in multigram quantities from enzymatic resolution, as a starting material, which transposes asymmetry through an Ireland-Claisen rearrangement.

The first total synthesis of (+)-5-epi-eudesm-4(15)-ene-1β,6β-diol has been achieved in 12 steps starting from the known (-)-cis-piperitol and by using a chelation controlled glycolate enolate Ireland-Claisen rearrangement and an intramolecular nitrile oxide dipolar cycloaddition as key steps.

α-Alkyl β-amino esters are available in high diastereoselectivity through a silicon-free Claisen enolate [3,3]-sigmatropic rearrangement of enamide esters. Optimisation studies have probed the crucial role of the initial enolisation and the nature of the enamide N-centre. The demonstration of chirality transfer and the formation of β-proline systems, is also presented.

Direct heating of a metal-organic framework provides a simple, controllable way of effecting a covalent post-synthetic modification. Herein we report that an allyloxy-tagged zinc metal-organic framework undergoes a thermally-promoted aromatic Claisen rearrangement through which the framework connectivity and porosity are maintained.