Konstitution und Reaktionen aliphatischer Carbonyl‐diazo‐Verbindungen

Abstract

Diazomethan reagiert mit den Dicarbonsauredichloriden C1. CO . (CH2),.CO. CI (n 2 3) glatt zu den entsprechenden Bis-diazo-ketonen N2CH.CO .(CH2),.CO. CHN2. Bei der analogen Umsetzung mit Oxalylchlorid (n = 0) und Bernsteinsauredichlorid (n = 2) werden 1.4-Bis-diazo-butandion-(2.3) bzw. 1.6-Bis-diazo-hexandion-(2.5) nur in maBigen Ausbeuten gewonnen. Die Reaktion der Dicarbonsauredichloride und -dibromide (n 2 4) rnit Diazoessigester laBt sich unter Verwendung oberflachenkatalytisch wirkender Stoffe (Siedesteinchen) so steuern, daR die Bis-diazo-ester R02C. CN2. CO . (CH& CO CN2. C02R (n = 4-7) kristallin erhalten werden. -Die wechselseitige Beeinflussung von Diazo-und Carbonylgruppe wird an Hand von IR-Spektren der Bis-diazo-Verbindungen N2CH.CO.(CH2),.CO.CHNz (n = 0,2-8), CH302C.CN2.CO. (CH2)n.C0.CN2.C02CH3 (n = 0,4-7) sowie analog gebauten Verbindungen diskutiert. -Hinsichtlich der Konstitution der von H. STAUDINCER aufgefundenen ,,Hydrazimethan"-Derivate (Diaziridine) aus Diazoverbindungen + Azoverbindungen wird auf synthetischem Wege gezeigt, daB dem Isomerisierungsprodukt des Diphenylen-hydrazimethan-dicarbonsaureesters die (offene) Hydrazon-Struktur zukomrnt. Die von E. MULLER dargestellten ,,Hydrazimethan"-Derivate werden auf ihre lsomerisierbarkeit untersucht. -Diazoketone R.CO.CHN2 konnen in die Ester R.CO.CH2.X auch solcher Sauren iibergefiihrt werden, die als freie Sauren nicht zuganglich sind oder auf Diazoketone zerstBrend wirken. Mit Mineralsauren (HzS04, HN03) in Gegenwart hoher Neutralsalz-Konzentrationen (KBr bzw. KSCN bzw. NaN03) werden die bisher unbekannten Broniketone B~CHZ.CO.(CH~),.CO.CH~B~ (n = 3-7), die Dioxo-dirhodanide NCS.CH2.CO.(CH2),.CO.CH2.SCN (n = 3-8) und die Dioxo-dinitrate 02N . O . CH2 .CO -(CHz),,.CO. CH2 .O .NO2 (n = 4-6) in guten Ausbeuten hergestellt. Liebigs AM. Chem. Bd. 638 1 2 E. FAHR Bd. 638 1 ) TH.

[2.2]‐ and [3.3]Tetrathiafulvalenophanes

“…In the temperature range investigated acetylene in reaction A is always formed together with ( 2 ) , while at 800°C it is the sole product. Dehydrobenzene is not observed in reaction B, even at 800 "C. From these experiments it cannot be decided whether acetylene is formed by direct fragmentation of (1) or via ( 2 ) , or in both ways concurrently. Figure 1 shows the PE spectra of the reactants (1) and (3) as well as those of the products (2) and acetylene and of (4).…”

“…In order to systematically vary the crystal lattice in charge transfer systems which could be of interest as electrical semiconductors or conductors by changing the moIecuIar architecture"], we synthesized [2.2]-and [3.3]tetrathiafuIvalenophanes ("TTF-phanes"). For these compounds the following structural and stereo-isomers are possible: 1) "paracyclophane-like" compounds with diagonal 4',4'-and 5,5-linkage, which may exist as an achiral stereoisomer with approximately parallel TTF "axes" and all corresponding Cand Satoms of the two TTF groups [ ( l ) and (3), respectively] in the eclipsed position as well as a chiral stereoisomer with crossed TTF axes which formally is derived from (1) and (3), respectively, by 180" rotation of one of the TTF units about the axis through the C-4/C-5 points of linkage; 2) "metacyclophane-like" compounds with 43and 4,5'-linkage I (2) and (4), respectively], whose TTF groups, as in the metacyclophanes, could be in a step-like anti-conformation and-less likely-in a syn-arrangement; 3) finally, TTF-phanes in which one TTF group is linked metacyclophane-like, the other paracyclophane-like (4,5-/4,4'-linkage). In the synthetic method employed by us, in which the central C---C double bonds of the TTF groups were formed in the last step''], in principle, all the structural and stereo-isomers could be formed.…”

“…On heating, cycloalkeno-l,2,3-~elenadiazoles are converted into cycloalkynes [']. 1,2,3-Selenadiazole (I) ['] can be transformed photochemically[31 (in matrix) and thermally[41 (in the gas phase) into the reactive selenoketene (2). We have now been able to generate for the first time the highly reactive 6-fulveneselone (4) from 1,2,3-benzoselenadiazole (3)14 in the gas phase by variable temperature photoelectron spectroscopy and flash vacuum thermolysis (VTPESC'"] and FVT15b1, respectively).…”

“…The PE spectra of ( I ) to (4) very closely resemble those of the corresponding sulfur compounds (1,2,3-thiadia~ole~~~~, thi~ketene"~], 1,2,3-ben~othiadiazole~~~~ and 6-fulvene-thi~ne['~], respectively). A comparison of the respective PE spectra and of the He1 and He11 spectraIsl provided a basis for the identification of (2) and (4) and for the following IPleVl -IPLeVl - Fig. 1.…”

Synthesis of the Proposed Structure of Sclerosporin with a Guaiane Skeleton

“…The acid 6 was converted to its bisdiazoketone 8 via an acyl chloride 7,5) which was cyclized by adding it to a solution of cupric acetylacetonate in hot benzene under a high dilution condition 6 ,7) to give an ene-dione 9 in a 14% yield from 6. Catalytic hydrogen- ation of 9 over palladium on carbon provided a cycloheptanedione 10 in a 95% yield.…”