caa a22 4500 469038950 CHVBK 20180323132804.0 cr unu---uuuuu 170328e19920101xx s 000 0 ger 10.1007/BF01045301 doi (NATIONALLICENCE)springer-10.1007/BF01045301 [2+2]-Photocycloaddition von Cyclohexen an 2-Acetyl-5,5-dimethyl-1,3-cyclohexandion und 3-Acetyl-1,5,5-trimethyl-2,4-pyrrolidindion [Elektronische Daten] [Hans-Georg Henning, Giedrius Mazunaitis] [2+2]-Photocycloaddition of cyclohexene to 2-acetyl-5,5-dimethyl-1,3-cyclohexanedione and 3-acetyl-1,5,5-trimethyl-2,4-pyrrolidinedion Summary: Irradiation of solutions of excess cyclohexene and 2-acetyl-5,5-dimethyl-1,3-cyclohexanedione (1), and 3-acetyl-1,5,5-trimethyl-2,4-pyrrolidinedione (4) results mainly in the formation of 1,5-diones2 and5. These originate from intermediate cycloadducts of cyclohexene and theexo-enols of the cyclic 1,3-diketones. The yields decrease with increasing polarity of the solvent. In solution2 and5 are in equilibrium with the cyclic hemiacetales3 and6. Springer-Verlag, 1992 [2+2]-Photocycloaddition nationallicence 2-Acetyl-5,5-dimethyl-1,3-cyclohexanedione nationallicence 3-Acetyl-1,5,5-trimethyl-2,4-pyrrolidinedione nationallicence 2-(2′-Acetyl-cyclohexyl)-5,5-dimethyl-1,3-cyclohexanedione nationallicence 3-(2′-Acetyl-cyclohexyl)-1,5,5-trimethyl-2,4-pyrrolidinedione nationallicence Henning Hans-Georg Institut für Organische Chemie, Humboldt-Universität Berlin, D-O-1040, Berlin, Bundesrepublik Deutschland aut Mazunaitis Giedrius Institut für Organische Chemie, Humboldt-Universität Berlin, D-O-1040, Berlin, Bundesrepublik Deutschland aut Monatshefte für Chemie / Chemical Monthly Springer-Verlag 123/1-2(1992-01-01), 93-98 0026-9247 123:1-2<93 1992 123 706 https://doi.org/10.1007/BF01045301 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF01045301 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Henning Hans-Georg Institut für Organische Chemie, Humboldt-Universität Berlin, D-O-1040, Berlin, Bundesrepublik Deutschland aut NATIONALLICENCE 700 1- Mazunaitis Giedrius Institut für Organische Chemie, Humboldt-Universität Berlin, D-O-1040, Berlin, Bundesrepublik Deutschland aut NATIONALLICENCE 773 0- Monatshefte für Chemie / Chemical Monthly Springer-Verlag 123/1-2(1992-01-01), 93-98 0026-9247 123:1-2<93 1992 123 706 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer