bromiden und -jodiden relativ einfach zu hoheren Diazocarbonsaure-athylestern (3) gelangt.(2) erhalt man aus Diazoessigsaure-athylester und Silberoxid bei 0 "C. Die thermolabile Verbindung konnte bisher nicht isoliert werden, verrat sich aber durch ihre charakteristische IR-Absorption bei 2040 cm-1 (Nz-Gruppe) und laI3t sich auBerdem durch Jod in Form des Jod-diazoessigsaure-athylesters [21 ( I ) abfangen.Beispielsweise erhielten wir P-Phenyl-cc-diazopropionsaureathylester (3), R = CsH5CH2, [Kp = 95 "Cjl Torr (teilweise Zers. zu Zimtsaure-athylester); IR: 2080 cm-1, 1685 cm-1; NMR (in CCld), 7 = 8,8 (t), 6,4 (s), 5,8 (q), 2,83 (m)] in ca. 6O-proz. Ausbeute, als wir die atherische Suspension von (2) mit Benzylbromid 10 Std. bei 0 bis 20 "C riihrten. P-Phenyl-a-diazopropionsaure-athylester geht beim Erhitzen in ein Gemisch von trans-und cis-Zimtsaure-athylester iiber. Damit zeichnet sich die Moglichkeit einer neuartigen, unter Kettenverlangerung verIaufenden Synthese a,P-ungesattigter Carbonsaure-ester ab. Die Existenz von (2) interessielt auch in theoretischer Hinsicht : Bei der AgzO-katalysierten Wolff-Umlagerung ist die Rolle des Katalysators noch ratselhaft [31. Nach unseren Befunden besteht diese Rolle sehr wahrscheinlich darin, das Diazoketon in sein Silberderivat iiberzufiihren, welches dann Abwandlung erleidet. 2-Diazo-pent-4-ensaure-athylester:Zu 5,l g (0,05 mol) Diazoessigsaure-athylester fugt man unter Riihren bei 0 "C in ca. 1,5 Std. portionsweise 5,8 g (0,025 mol) Silberoxid (je 0,5 g) und verdunnt allmahlich mit insgesamt 60 ml Ather. Nach 3-stdg. Riihren bei 0 "C iropft man unter Eiskuhlung 12,6 g (0,075 mol) Allyljodid zu und ruhrt 3 Std. bei 0°C. Man filtriert, trocknet das Filtrat iiber Natriumsulfat, engt im Rotationsverdampfer ein (13 Torr, 40 "C) und fraktioniert.

On high-temperature synthesis of amino acids from methane, ammonia, and water vapor we have found numerous intermediates as well as three amino acids (lysine, tryptophane, and p-alanine) whose formation had not previously been reported 11-31. We obtained the best yields of amino acids in a streaming apparatus under the following conditions: CH4 0.5 I!min, NH3 0.3 l/min, and H20 0.2 I/min; the residence time of the gases in the reaction zone was 0.125 sec; warming of the gases from 100 to 800 "C required 0.28 sec, and cooling to 20 OC required 0.4 sec; the optimal temperature in the reaction zone was 1000°C, 95.4% of the NH3 in the reaction mixture then undergoing conversion. Yields of amino acids were very low at 9OO0C, and at 115OoC the methane was converted into graphite. At 1050 "C aromatic hydrocarbons and oxygen compounds (mainly acetaldehyde and propionaldehyde) constituted up to 1 % of the total product; at this temperature the proportion of nitrogen compounds (methylamine, ethylamine, hydrogen cyanide) amounted to 10 mole-"/,. The reaction zone was filled with silica gel (particle size 3 to 6 mm).The products of synthesis were identified by gas chromatography and the individual amino acids by high-voltage paper electrophoresis (50 V/cm).The compounds identified are listed in the following table. The differing rates of the light-induced valence isomerizations ( I ) + (2) and (3) + (4) have been ascribed to the differing overlaps between the x-and the h-orbitals [" in ( I ) and (3) [2J.We have now isomerized compounds of type (5) photochemically to the corresponding pentacyclic compounds (6). Compound (6.) is not formed in isolable amounts under the conditions that are optimal for the change ( I ) + (2) (R = COzH; yield in water > 90%); further, the yield of (6b) is only a few percent when the ester (Sb) is irradiated in ether.However, isomerization of (5b) in glacial acetic acid and of (5u) in this solvent, dioxane, or in tetrahydrofuran-ether ( 5 : l to 7:4)[31 can be achieved, giving (so far) yields ofThe structure of (6.) is proved by the several reactions The pentacycles (6b) and (7) are very stable thermally. For instance, heating (66) alone or in dimethyl acetylenedicarboxylate (300OC) does not cause isomerization to (56) or