Dimethyl Cubane-1,4-dicarboxylate: A Practical Laboratory Scale Synthesis

Abstract

Complete experimental details for the preparation of dimethyl cubane-1,4-dicarboxylate (1) in multigram quantities, from cyclopentanone (2), in an overall yield of c. 23% are presented.

Highly Strained Tertiary sp3 Scaffolds: Synthesis of Functionalized Cubanes and Exploration of Their Reactivity under Pd(II) Catalysis

“…Protected (hydroxymethyl)cubanes were chosen as the basis for this work both to avoid issues relating to isolation of products (as the polarity of Bu-R and cubane-R can be very similar) and to provide a synthetic handle for further substitution reactions. Halogenated (hydroxymethyl)cubanes were prepared by known methodologies 23,[25][26][27] and protected with appropriate groups. While more standard protecting groups proved equally effective, the majority of this work involved protection of the free hydroxyl group as a methyl ether.…”

“…27 This was converted to methyl 4-iodocubanyl-1-carboxylate and reduced through known procedures. 42 Iodocubane 23 was synthesized by Eaton's procedures from appropriate precursors.…”

Nonconjugated Hydrocarbons as Rigid‐Linear Motifs: Isosteres for Material Sciences and Bioorganic and Medicinal Chemistry

“…[56] Eaton's originals ynthesis of the carbon skeleton of cubane 37 is still the basis of most practical approachest oi nstall the caged structure. [57] Just two cycloadditions, ad iastereoselective Diels-Alder reaction, and as ubsequent [2+ +2]-photocyclization, are necessary to setup the backboneo fc ubane, which then can undergo ad oubler ing contractionu nder Favorskii conditions (Scheme 9). [53] Other approaches to generate substituted cubanes, make use of [2+ +2]-cycloadditions of substituted tricy-clo[4.2.0.0 2,5 ]octa-3,7-diene derivatives 38,amethodn ot suitable for unsubstituted cubanes, due to the large separation of the involved p-orbitals( 3.05 ), the sizeable differencei ns train energy between the educt and product, and ad ominance of through-bond interaction, as p + lies above p À forb oth sets of MOs (Scheme 10).…”

Decagram Synthesis of Dimethyl 1,4-Cubanedicarboxylate Using Continuous-Flow Photochemistry

“…Using key elements from Eaton's and Chapman's approaches, Tsanaktsidis et al reported in 1997 an optimised practical laboratory synthesis of dimethyl 1,4-cubanedicarboxylate (1) on a decagram-scale (Scheme 2). 22 Following Chapman's synthesis of 12, full deprotection led to Eaton's diketone 6 allowing the photochemical step to be conducted on 50 gram scale with a 450 W mercury lamp in a batch photoreactor, although the irradiation time was not reported. 22 Moreover, Tsanaktsidis and co-workers obtained an improvement of the double ring contraction rearrangement, reporting that higher yields could be obtained when ≤12 mL of 25% aqueous NaOH per gram of 7 was used.…”