Nucleophilic Attack on the 3-Phenyl-4-sulfidocyclobutenediylium-1 2-diolate Anion.код для вставкиСкачать
principle, the resulting alkyl radical (6) could spontaneously rearrange into radical (7). However, if the homologous radical (8) is generated by decarbonylation of the corresponding aldehyde no rearrangement takes place[*]. H3C\ /COOCzH5 HSC ,C00C2H5 H3C\ COOCzH5 C-H I HZ COOCzH5 14) 151 + /C\ I CHz-COOCzH5 7 b and mass spectrometry. The residue which cannot be extracted with pentane contains still unreacted (3) in most cases. Received: October 2, 1975 [Z 328 IE] German version: Angew. Chem. 87.877 (1975) [l] For a review, see W Friedrich in R. Ammon and W Dirscherl: Vitamin B I Zund verwandte Corrinoide. Thieme, Stuttgart 1975.  G. N. Schraurer, Acc. Chem. Res. I, 97 (1968); G. N. Schrauzer and J . W Siberr, J. Am. Chem. SOC.92, 1022 (1970).  H. Eggerer, P. Overath, F . Lynen, and E. R . Stadtman, J. Am. Chem. SOC.82,2643 ( I 960).  R . W Kellermeyer and H. G . Wood, Biochemistry I, 1124 (1962); E. F. Phares, M . K Long, and S . F. Carson, Biochem. Biophys. Res. Commun. 8, 142 (1 962).  R. H. Abeles and B. Zagalak, J. Biol. Chem. 241, 1245 (1966); P. A . Frey, M . K . Essenberg, and R . H . Abeles, ibid. 242, 5369 (1967). 161 J . RPtey and D. Arigoni, Experientia 22, 783 (1966); G. J . Cardinale and R . H. Abeles, Biochim. Biophys. Acta 132, 517 (1967).  For a review, see D. G. Brown, Progr. Inorg. Chem. 18, 207 (1973).  S. N. Lewis, J. J . Miller, and S . Winsrein, J. Org. Chem. 37, 1478 ( 1972).  P. Dowd, M. Shapiro, and K . Kang, J. Am. Chem. SOC.97,4754 (1975). It is not clear from this publication whether it is the acrylyl or the tetrahydropyranyloxycarbonylwhich migrates. [lo] Prepared from diethyl methylmalonate and dibromomethane with 1 mol of base. [ I l l Nore added in proof' (Nov. 13, 1975): The cobalamin complex corresponding to (3) is so unstable that it decomposes in the dark at pH 7 within a few hours, affording (4) and (5). Hz$ Nucleophilic Attack on the 3-Phenyl4sulfidocyclobutenediylium-l,24iolate Anion[**] Regardless of the role the central cobalt atom and its trans ligand (pyridine)play in the rearrangement of ( 3 ) , an analogy with the coenzyme B1,dependent transformation of methylmalonyl-CoA ( 1 ) into succinyl-CoA ( 2 ) appears compelling. Further characterization of the model reaction will show whether the analogy can be pursued to greater depths. After having obtained the present results, we learned that Dowd et aLi9] have observed a similar rearrangement in a system different from ours[' 'I. By Arthur H. Schmidt, Walter Ried, Peter Pustoslemsek, and Waiter Schuckmann[*] The 4-sulfidocyclobutenediylium-I ,2-diolates (1 a) and (1 b)"] belong to a new class['*2] of four-membered carbocycles displaying 2sc-electron delocalization, in which oxygen and sulfur bear the negative charge in the anion. As expressed in formula (1 ) the anion possesses electrophilic character; it should therefore react with nucleophilic reagents. 2,2-Dietkoxycarbonylpropyl(pyridinato)cobaloxime ( 3 ) To a solution of CoCI, .6 H z 0 (1 mmol) and biacetyldioxime (2mmol) in anhydrous ethanol (99.85 %) are added potassium hydroxide (2 mmol) and pyridine (1 mmol), both in the form of 1 M alcoholic solutions. After stirring for 15 min at 25 "C the solution is purged with argon and cooled to -10°C. Potassium hydroxide (1 mmol) and NaBH, (2 mmol) are then added under argon in the dark, the argon replaced by hydrogen, and the mixture allowed to react for 1 h at - 10°C. After warming to 25 "C, diethyl 2-bromomethyl-2-methylpropanedioate['"] (5 mmol) is added to the stirred reaction mixture. The black solution turns light orange. After 15 min the solvent is removed under vacuum, the residue taken up in dichloromethane, and filtered under nitrogen. Chromatography on silica gel with ethyl acetate as eluant affords 393 mg (0.71 mmol) (3). (Beautiful orange-red needles from methanol/ water + one drop of pyridine.) NMR (100 MHz, CDCI,): 6=1.18t (6H); 1.30s (3H); 2.00s (2H); 2.12s (12H); 4.09 double sextet (4H); 7.32m (2H); 7.75t (IH); 8.56d (2H). Compound (3) gave a correct elemental analysis. Example of photochemical reaction of ( 3 ) Compound (3) (4 mg, 7.2 pmol) is dissolved in anhydrous ethanol (1 ml) containing 1 % of acetic acid with half-an-hour's stirring in the dark under argon. The solution is maintained at 15-20°C during 90 minutes' irradiation with a high pressure mercury lamp (125 watt, Philips) at a distance of 8cm. After removal of solvent under vacuum, the residue is extracted with pentane and the extract analyzed by gas chromatography Angrw. Chem. inrurnur. Edif. Vol. 14 (1975) 1 No. 12 Surprisingly,however, heating of (1 b) with aliphatic amines merely affords ammonium salts such as (1 c ) , thus underlining the pronounced acidity"] of (lb). In contrast, reaction of equimolar solutions of (1 a) or (1 b) with primary aromatic amines (THF; ethanol) leads to deeply colored condensation products (2)-(5), even when the reaction is performed in an ice-cold medium. Thus the electrophilic character of system ( 1 ) is confirmed and atom C-4 is ruled out as the point of attack by nucleophiles. The IR spectrum of (4) (Table 1) suggests a delocalized bond system13]as a structural component of the novel class of compounds. Apart from the expected absorptions, the 'H-NMR spectra of ( 2 ) and ( 5 ) contain the broad signal due to a single proton at low field [*I Dr. A. H. Schmidt ['I, Prof. Dr. W. Ried, and DipLChem. P. Pustoslemsek Institut fur Organische Chemie der Universitat 6 Frankfurt/Main, Theodor-Stern-Kai 7 (Germany) Dr. W. Schuckmann Institut fur Kristallographie der Universitat 6 Frankfurt/Main, Senckenberganlage 30 (Germany) ['I To whom correspondence should be addressed. [**] Reactions with Cyclobutenediones,Part 43.-Part 42: W Ried, H. Knorr, and U . Knorr, Chem. Ber., in press. 823 hydrogen carbonate and can be regenerated unchanged by cautious acidification. If (2) is added to cyclohexylamine and the ice-cold solution treated with dilute sulfuric acid then ( 1 c ) is obtained. This suggests the intermediacy of the salt (6) and emphasizes its ease of hydrolysis. The action of diazomethane on (2) affords the thioether (7). Cautious hydrolysis permits its degradation to (8)"l. Treatment of a solution of (2) in THF with an aqueous solution of HgC12 immediately precipitates the mercury salt (9) which fulfils the conditions necessary for inner chelate Table 1. Properties of 2-arylamino-4-phenyl-3-sul8docyclobutenediylium-l-olates (2)-(5) are available for all compounds.  and of compounds (7) and (9). Satisfactory elemental analyses 'H-NMR [6, ppm] Cpd. Ph = CbH5 Ar M. p. r C ] solvent, color IR [cm-'1 [a] (2) CsH5 212-215 ethanol, red (3) 2-Br-C6H4 (4) 4-CHs-ChHd (5) 4-OCH3-CrjHd 178-1 80 benzene, dark red 206 acetonitrile, red 200-202 benzene, red 129 ethanol, yellow 3165-2850 br, 1780 w, 1735 s, 1705 sh, 1650 w, 1590 w 1725 s, 1700 w, 1620 s, 1570 s, 1550 m (7) 350 (dec.) 191 - 9.9-10.3 [b] 3190-2680 br, 1720 w, 1700 s, 1620 s, br, 1585 sh, 1570 m 11.6-12.0 [b] 3060 w, 2970 w, 2820 w. 1740 s, 1655 m 7.88-7.69 6.94-7.50 3.09 (2 H, m) (8 H, m) (3 H, s) [c] 3180-2700 br, 1720 w, 1700 s, 1625 sh, 1610 s, br, 1570 m 3060 w, 1750 s, 1655 m, 1500 m yellow [a] s=strong, m=medium, w=weak, sh=shoulder, b=broad. [b] 60 MHz, [D,]-DMSO, acidic H. [c] 100 MHz, CDC13. which undergoes ready exchange with D20. The mass spectrum of (2) is not very characteristic. Since the spectroscopic data of the condensation products were insufficient to permit a distinction between the structures (2)-(5) and the 2-substituted isomers, compound (3) was subjected to X-ray structure analysis[51.The result confirmed the structures (2)-(5) and hence C-1 as the site of nucleophilic attack on the 3-phenyl-4-sulfidocyclobutenediylium-1,2diolate anion. The molecular diagram15]of (3) reveals furthermore that the four-membered ring system is planar and that the four substituents lie in the same plane. Accordingly, the linkages between the four different substituents and the fourmembered ring system are formed by double bonds and partial double bonds. Compounds ( 2 ) - - ( S ) are characterized by their high acidity. They are readily soluble in a 10% solution of sodium formation between the lone pairs of the nitrogen and the mercury atom. Hydrolysis of (2) with concentrated hydrochloric acid leads to (I b) (see Table 1 for properties of the new compounds). Received: September 12, 1975; revised: October 15, 1975 [Z 329 IE] German version: Angew. Chem. 87.879 (1975) A. H . Schrnidt, W R i a l , P. Pustoslmmsek, and H . Dietschmarin, Angew. Chem. 84, 110 (1972); Angew. Chem. internat. Edit. 1 1 , 142 (1972). a ) D. Coircoucanis, F. Hollander, R . West, and D. Eggerding, J . Am. Chem. SOC.96, 3006 (1974); b) G. Seit;, H . Morck, K . Mann, and R . Schriiiedelel, Chem.-Ztg. 98. 459 (1974): c) G. Seitz. K . Mormn. R. Sc/mrimiedel. and R. Marusch, ibid. 99, 90 (1975). W Ried, A. H . Schmidt, G. Iserihrirck, and F. B a t i , Chem. Ber. 105, 325 ( 1972). Of the three resonance formulas of compounds ( 2 ) - ( 5 ) we employ the central one for purposes of description and designation. W Schirckmann. P. Pirstoslerimsek, W Ried, and A. H . Schrnirlr, to be published. Simple Synthesis of 1-Halobicyclooctanes~**l [***I f2) + CHzNa - phmsCH3 PhwsCH3 + HCI 'Ph 824 By Wolfgang Kraus and Hans-Dieter GrafI'[ Dedicated to Professor Eugen Muller on the occasion of his 70th birthday We have found that 1-halobicycloalkanes are formed in very good yield from corresponding bridgehead tosylates on [*] Prof. Dr. W. Kraus and Dr. H.-D. Graf Chemisches Institut der Universitat Tiibingen Present address: Lehrstuhl fur Organische Chemie der Universitat Hohenheim 7 Stuttgart 70, Emil-Wolff-Strasse 14 (Germany) [*'I Part of Doctoral Dissertation of H . - D . Graif. Universitat Tiibingen 1975. [***] This work was supported by the Fonds der Chemischen Industrie.