19785-02-5Relevant academic research and scientific papers
High pressure nucleophilic fluoride-ion substitution reactions: Formation of fluoroalkylbenzenes
Gerdes, John M.,Keil, Robert N.,Shulgin, Alexander T.,Mathis, Chester A.
, p. 121 - 129 (1996)
A series of 1-phenyl-2-tosyloxy- and 1-phenyl-3-tosyloxyalkanes was synthesized and then subjected to tetrabutylammonium fluoride in THF under 15 kbar (1.5 GPa), 8 kbar or 1 bar pressures. The resultant substitution and elimination reaction product distributions were analyzed. The application of pressure enhanced the progress of the fluoride-ion substitution reactions. The degree of selectivity of the one reaction over the other was found to be a function of tosylate substrate structure and the amount of pressure applied. The exclusive formation of fluoroalkanes from 1-phenyl-2-tosyloxyalkane substrates under 15 kbar pressure demonstrated the potential of the pressure method for prospective use in fluorine-18 radiolabelling applications.
Stereoselective isomerisations of 4-(2′,5′-dimethoxyphenyl)-2,5-dimethyl-1,3-dioxolanes and their 2′-chloro-5′-methoxyphenyl analogues. Temperature-dependent diastereoselective formation of isochromanes
Giles, Robin G. F.,Rickards, Rodney W.,Senanayake, Badra S.
, p. 3361 - 3370 (2007/10/03)
Stereoselective isomerisations of rel-(2R,4S,5R)-4-(2′,5′-dimethoxyphenyl)-2,5-dimethyl-1,3-dioxolane 1 and the 2:1 epimeric mixture of rel-(2S,4R,5R)- and rel-(2R,4R,5R)-4-(2′,5′-dimethoxyphenyl)-2,5-dimethyl-1,3-dioxolanes 2 and 3 with titanium tetrachl
Oxocarbons and related compounds. 27. Synthesis of dihydrocyclobuta[a]naphthalene-1,2-diones and cyclobuta[a]naphthalene-1,2-diones via annulation of alkoxy-(1-alkenyl)benzenes with 3-chloro-3-cyclobutene-1,2-dione. Scope and limitations
Schmidt, Arthur H.,Kircher, Gunnar,Spring, Mathias,Hendriok, Markus W.,Kuenz, Christian
, p. 564 - 574 (2007/10/03)
The reaction of alkoxy-(1-alkenyl)benzenes with semisquaric chloride (3) has been investigated systematically. 1,2-Dialkoxy- and 1-alkoxy′-2-alkoxy″-4-(1-alkenyl)benzenes (6a-j) and (11a-i) react with 3 to give the 3,4-dihydrocyclobuta[a]naphthalene-1,2-diones(8a-j) and (12a-i). Treatment of the dihydrocyclobuta[a]naphthalene-1,2-diones with 1.2 equiv. bromine effects dehydrogenation and affords cyclobuta[a]naphthalene-1,2-diones(9a-e) and (13b-f). Any efforts to extend this annulation reaction to dimethoxy-(1-alkenyl)benzenes with the methoxy groups in other than the 1,2-positions, e. g. 14a, b, 16a, b have been unsuccessful. The reaction of 1,2,3-trimethoxy-4-(1-propenyl) [and 4-(1-butenyl)]-benzenes (18a) and (18b) with semisquaric chloride (3) leads to the elimination of HCl and CH3OH and gives 5,6-dimethoxy-3-methyl [and 3-ethyl]-cyclobuta[a]naphthalene-1,2-diones (20a) and (20b). The reaction pathway of this novel annulation reaction is discussed.
