53783-91-8Relevant academic research and scientific papers
Solvent-induced stereospecific isomerization of an allylic alcohol to a homoallylic alcohol catalyzed by a chiral lithium amide
Arvidsson, Per I.,Hansson, Maria,Khan, Agha Zul-Qarnain,Ahlberg, Per
, p. 795 - 799 (1998)
Deprotonation of cyclohexene oxide, 1, by lithium (S)-2-(1- pyrrolidinylmethyl)pyrrolidide, 2-Li, on changing the solvent from tetrahydrofuran (THF) to, for example, 2,5-dimethyltetrahydrofuran (DMTHF) or diethyl ether (DEE) has been shown to yield, besid
Alkylhalovinylboranes: a new class of Diels-Alder dienophiles
Pisano, Pablo L.,Pellegrinet, Silvina C.
, p. 33864 - 33871 (2018/10/20)
The Diels-Alder reactions of alkylhalovinylboranes have been investigated theoretically and experimentally. Alkylhalovinylboranes presented higher reactivity than the corresponding dialkylvinylboranes. Although endo/exo selectivities were high for the reactions with cyclopentadiene, facial selectivities for the chiral analogues were low. Our results demonstrate that the replacement of an alkyl group on the boron atom by a halogen increases the dienophilicity considerably.
Evaluation of the use of mandelate derivatives to determine the enantiomeric purity and the absolute configuration of secondary cyclohexenols
Sarotti, Ariel M.,Pisano, Pablo L.,Pellegrinet, Silvina C.
body text, p. 343 - 357 (2011/06/10)
The use of mandelate derivatives to determine the enantiomeric purity and the absolute configuration of isomeric mixtures of bicyclic and monocyclic secondary cyclohexenols was investigated. Synthesis, NMR and conformational analyses of the derivatives were performed and Gauge-Independent Atomic Orbital (GIAO) 1H NMR Boltzmann weighted average chemical shifts were computed. The studied methodology proved to be of practical value for most of the systems under study. ARKAT-USA, Inc.
A facile microwave-assisted Diels-Alder reaction of vinylboronates
Sarotti, Ariel M.,Pisano, Pablo L.,Pellegrinet, Silvina C.
supporting information; experimental part, p. 5069 - 5073 (2010/12/25)
The Diels-Alder reaction of vinylboronates can be easily performed using microwave irradiation giving excellent yields of the cycloadducts. Pinacol vinylboronate was the reagent of choice due to its stability towards hydrolysis, operational simplicity and yields of Diels-Alder products. To the best of our knowledge, this is the first example of microwave-assisted Diels-Alder reaction of boron-substituted dienophiles. Subsequent in situ oxidation of the cycloadducts with alkaline hydrogen peroxide afforded the alcohols efficiently.
Stereoselective solvent induced 1,3-proton transfer of an allylic alkoxide to a homoallylic alkoxide catalysed by a chiral lithium amide
Hansson, Maria,Arvidsson, Per I.,Nilsson Lill, Sten O.,Ahlberg, Per
, p. 763 - 767 (2007/10/03)
Stereoselective rearrangements of e.g. meso-epoxides by chiral lithium amides yield chiral allylic alcohols in high enantiomeric excess. Such products are useful synthetic intermediates. Lithium (S)-2-(pyrrolidin-1-ylmethyl)-pyrrolidide Li-2 has been foun
Syntheses with organoboranes. IX. Vinyl- and 1-alkenyldichloroboranes as ethylene and 1-alkene equivalents for the Diels-Alder reaction
Zaidlewicz, Marek,Binkul, Jacek R.,Sokol, Wojciech
, p. 354 - 362 (2007/10/03)
Vinyl- and 1-alkenyldichloroboranes were used as dienophiles for the Diels-Alder reaction with representative aliphatic and cyclic 1,3-dienes. The organoborane adducts were transformed into the corresponding olefins either by protonolysis or by oxidation-mesylation-reduction. Direct protonolysis of the adducts gave in most cases mixtures of olefins whereas the reduction of mesylates with lithium triethylborohydride produced pure olefins in good yields.
2-Methyl Substituent Effects in the Antihomoaromatic Cyclopropinden-1-yl Cation
Friedrich, Edwin C.,Lucca, George De
, p. 4563 - 4567 (2007/10/02)
The rates and products of hydrolysis of the endo- and exo-2-methylcyclopropinden-1-yl 3,5-dinitrobenzoates in 80percent aqueous acetone have been determined.These are compared with similar data for the corresponding unsubstituted esters and for the 1-methyl-substituted and unsubstituted endo- and exo-2-bicyclohexyl 3,5-dinitrobenzoate model systems.This was done in connection with reports that toward acid-catalyzed epimerization in 50percent aqueous dioxane at 80 deg C 2-methyl substitution caused a 250-fold rate deceleration in the endo-cyclopropinden-1-ol system.For the endo 3,5-dinitrobenzoates the 2-methyl substituent did produce a rate decrease; however, this was only by a factor of about 1.2 at 80 deg C.In the 2-bicyclohexyl model system, the corresponding 1-methyl substitution caused approximately a 2-fold rate increase.
