96194-82-0Relevant articles and documents
Thermally responsive dendrons and dendrimers based on reversible furan-maleimide diels-alder adducts
McElhanon, James R.,Wheeler, David R.
, p. 2681 - 2683 (2007/10/03)
(Equation presented) Benzyl aryl ether dendrons and dendrimers containing thermally reversible furan-maleimide Diels-Alder adducts were prepared up to the third generation. The covalent cleavage and reassembly of the dendrons and dendrimers were evaluated by 1H NMR.
An Exploratory Study of Type II [3 + 4] Cycloadditions between Vinylcarbenoids and Dienes
Davies, Huw M. L.,Calvo, Rebecca L.,Townsend, Robert J.,Ren, Pingda,Churchill, R. Melvyn
, p. 4261 - 4268 (2007/10/03)
The intramolecular type II [3 + 4] cycloaddition between vinylcarbenoids and furans is a practical method for the construction of 5-oxo-10-oxatricyclo[6.2.1.04,9]undeca-3,8(11)-dienes, containing two anti-Bredt double bonds. These tricyclic systems are well functionalized for eventual elaboration to the natural product CP-263,114. The rhodium-stabilized vinylcarbenoids are generated by dirhodium tetracarboxylate catalyzed decomposition of vinyldiazoacetates. The [3 + 4] cycloaddition is generally considered to occur by a tandem cyclopropanation/Cope rearrangement, although evidence is presented that with these substrates the [3 + 4] cycloaddition may occur in a concerted manner.
Synthesis and assembly of new molecular hosts: Solvation and the energetics of encapsulation
Meissner,Garcias,Mecozzi,Rebek Jr.
, p. 77 - 85 (2007/10/03)
Experimental details are given for the preparation of 'softballs', large self-complementary molecules capable of assembly into pseudo-spherical capsules. Evidence is presented for their existence as hydrogen bonded dimers in organic solvents, and binding affinities for the reversible encapsulation of smaller molecules of suitable size and shape are given. Studies at various temperatures result in calculated enthalpies and entropies of encapsulation that are positive; accordingly, the process is entropy driven. It is proposed that the hosts in their resting states contain two molecules of solvent such as benzene, and the encapsulation of a single large guest-the hostage-liberates the two solvents. The resulting increase in the number of free molecules gives rise to the increase in entropy observed for the exchange process. Experiments involving solvent mixtures are consistent with this rationale. Calculation of the capsule's interior volume and molecular dynamics simulations support the experimental observations, and hint at unexpected phenomena dealing with the occupancy factors of these systems.