J. A m . Chem. SOC.1984, 106, 2651-2655 isooctane/ether, 1/1, to give 5.8 g (47%) of 2,3-diethylmaleimide: mp 69-70 "C (lit.47mp 68 O C , lit.48 mp 68-70 "C); R, (GC) 3.30 min. cis -3,4-Diethylpyrrolidine-2,5-dione(cis-2,3-Diethylsuccinimide). To 180 mg (0.85 mmol) of the above 3,4-diethyl-lH-pyrrole-2,5-dione in 10 mL of ethyl acetate was added 18 mg of PtO,. Hydrogen at 50 psi was applied for 6 h,?! the solution was filtered through Celite, and the filtrate was evaporated to give 132 mg (100%) of residue. GC analysis showed a 95/5 mixture of cis/trans isomers which may be due to epimerization during analysis, as the cis compound was never found completely free of the trans by GC a n a l y s i ~ . ~ " The product was recrystallized from M e O H / H 2 0 and sublimed at 70 OC/l torr to give a 98/2 ratio of &/trans 2,3-diethylsuccinimide as white crystals: mp 87-89 "C; R, (GC) cis 5.16 min, trans 4.17 min; UV, , A, (log e) 246 (1.93), 221 nm (2.28); IR (KBr) 3130, 1670, 1340 cm-'; N M R (CDCI,, 90 MHz) 6 1.02 (t, 6 H, 2 X CH2CH3,J = 7.5 Hz), 1.54-1.77 (m, 4 H , 2 X CHICH3), 2.70-2.83 (m, 2 H, 2 X CH), 8.32 (br, s, 1 H , NH). Anal. Calcd for C 8 H I 3 N o 2 :C, 61.9; H, 8.4; N , 9.0. Found: C, 61.9; H , 8.4; N , 8.8. trans -3,4-Diethylpyrrolidine-2,5-dione (trans-2,3-Diethylsuccinimide). To the above cis-3,4-diethylpyrrolidine-2,5-dione (1 53 mg, 1 .OO mmol) was added a solution of 2.24 g (2.00 mmol) of potassium tert-butoxide in 60 mL of tert-butyl alcohol. After refluxed for 2 h, the solution was cooled and the tert-butyl alcohol was evaporated. Aqueous 1 M H 3 P 0 4 (20 mL) was added and the aqueous phase was extracted with CH2C12 (5 X 10 mL) which was dried and evaporated to give 143 mg (93%) of trans-2,3-diethylsuccinimide,mp 59-60 O C after recrystallization from H 2 0 and sublimation at 70 OC/l torr: R, (GC) 4.17 min; UV, , ,A (log e) 244 (1.64), 220 nm (2.22); IR (KBr) 3140, 1670, 1175 cm-I; N M R (CDCl3, 90 MHz) 6 1.00 (t, 6 H, 2 X CHICHI, J = 7.5 Hz), 1.60-1.90 (m. 4 H, 2 X CH2CH3),2.42-2.53 (m, 2 H, 2 X CH), 8.80 (br, s, 1 H, N H ) . Anal. Calcd for C8HIjNO2: C, 61.9; H, 8.4; N , 9.0. Found: C, 62.2; H, 8.4; N , 8.9. 3-Ethyl-4-methyl-IH-pyrrole-2,5-dione (2-Ethyl-3-methylmalei n ~ i d e ) . ' ~ . ~This ~ , ~compound ~ was prepared from 3-ethyl-4-methylpyrrole20*21,S2 as described for the 3,4-diethyl- lH-pyrrole-2,S-dione above
(50) Petryka, Z. J.; Watson, C. J . Tetrahedron Lett. 1967, 5323. (51) Muir, H. M.; Neuberger, A. Biochem. J . 1949, 45, 163. (52) Fischer, H.; Orth, H. 'Die Chemie des Pyrrols"; Adademische Verlagsgesellschaft M . B. H.: Leipzig, 1934; Vol. I p 49.
265 1
in 45% yield: mp 66-68 O C (lit.15mp 66-67 O C ; lit!' mp 67-68 OC; lit.51 mp 68 "C); Rf (TLC) 0.89. cis -3-Ethyl-4-methylpyrrolidine-2,5-dione(cis -2-Ethyl-3-methyls u c ~ i n i m i d e ) . ' ~This ~ ~ ~compound was prepared as described15 in quantitative yield: mp 48-50 OC (lit.31mp 50 "C); R f (TLC) cis 0.20, trans 0.30; R, (GC) cis 1.9 min, trans 1.3 min." trans -3-Ethyl-4-methylpyrrolidine-2,5-dione (trans -2-Ethyl-3methylsuccinimide)." This compound was prepared in an analogous manner to the trans-3,4-diethylpyrrolidine-2,5-dione above in 64% yield: mp 57-59 O C (lit." mp 60-61 "C); Rf (TLC) 0.30; R, (GC) 1.3 min. Bile Pigment Oxidative degradation^.?^ To a solution of 250 mg of Na2Cr207in 6 mL of H 2 0 was added 10 mg of the bile pigment ip 2 mL of THF. The oxidation was allowed to proceed at room temperature for 2 h, then 10 mL of H 2 0 was added, and the mixture was extracted with CH2C12( 5 X 10 mL). The combined organic phase was dried and evaporated. The residue of oxidation products from the octaethyldioxotetrapyrrole was analyzed by GC. In addition to the succinimide and maleimide products, an incomplete degradation product appears with a R, 8.30 min. The oxidation products from the bile pigments 20a, 20b, 21a, and 21b were analyzed by TLC.33,34,37 In addition to the succinimide and 2-ethyl-3-methylmaleimide, 3-(2-(methoxycarbonyl)ethyl)-4(hematinic acid methyl ester) was seen at methyl-lH-pyrrole-2,5-dione R f 0.50.
Acknowledgment. T h i s work was supported in p a r t by t h e Division of Biological Energy Conversion and Conservation ( D O E ) a n d t h e National Institute of General Medical Sciences, D H H S , GM 28994. T h e 360-MHz NMR studies were carried out a t t h e University of California, Davis, NMR Facility, under the auspices of N a t i o n a l Science Foundation G r a n t CHE 79-04832. Registry No. 7, 77469-08-0; 8, 89279-27-6; 9, 89279-28-7; 10, 89279-29-8; 11, 89361-42-2; 12, 89361-43-3; 13a, 766-45-0; 13b, 76636-9; 14, 53751-01-2; E a , 89279-30-1; 15b, 7761 1-80-4; 16a, 3140215-0; 16b, 77611-79-1; 17a, 13129-05-0; 17b, 13129-09-4; 18a, 8936144-4; 18b, 89361-45-5; 19a, 89361-46-6; 19h, 89361-47-7; 2Oa, 8936148-8; 2Ob, 89361-49-9; 2la, 89361-50-2; 2lb, 89361-51-3; 3,4-diethylpyrrole, 16200-52-5; 3,4-diethyl-3-pyrrolinone, 6065 1-43-6; 3,4-diethylIH-pyrrole-2,5-dione, 34085-07-9; cis-2,3-diethylsuccinimide, 892793 1-2; trans-2,3-diethylsuccinimide,89279-32-3.
Catalytic Cleavage of Active Phosphate and Ester Substrates by Iodoso- and Iodoxybenzoates Robert A. Moss,* K. W. Alwis, and Jae-Sup Shin Contribution from the Wright and Rieman Laboratories, Department of Chemistry, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08903. Received October 17, 1983. Revised Manuscript Received December 13, 1983
Abstract: p-Nitrophenyl acetate, p-nitrophenyl hexanoate, and p-nitrophenyl diphenyl phosphate ( P N P D P P ) were cleaved by o-iodosobenzoate, o-iodoxybenzoate, and 5-(n-octyloxy)-2-iodosobenzoate(3) in aqueous micellar cetyltrimethylammonium chloride solutions at p H 8. The system 3 / C T A C I was the best catalyst and P N P D P P was the most reactive substrate. In a remarkably rapid hydrolytic reaction a t 25 OC, 1.0 X M P N P D P P was cleaved by 7.14 X M 3 in 2.0 X M CTACl with k , = 1.04 s-I. Experiments in which [PNPDPP] > [3] demonstrated that the catalyst "turned over"; Le., degradation of an intermediate phosphate was not rate limiting.
W h e n solubilized in pH 8 micellar cetyltrimethylammonium chloride ( C T A C I ) , o-iodosobenzoate (1) is an efficient catalyst
catalytic power is l-hydroxy-l,2-benziodoxolin-3-one (1,3-dihydro- 1-hydroxy-3-oxo- 1,2-benziodoxoIe) (2) t h e valence tautomeric f o r m in which 1 prefers t o exist2 a n d which appears t o be a powerful 0 nucleophile. In this full report, these results a r e (1) Moss, R. A.; Alwis, K. W.; Bizzigotti,G. 0.J . A m . Chem. Soc. 1983,
I
1
02
for the
p-nitrophenyl acetate (PNPA) and pmnitrophenyl diphenyl phosphate ( P N P D P P ) . ' T h e a c t u a l source of Of
0002-7863/84/ 1506-2651$01.50/0
105. 681.
(2) (a) Meyer, V.; Wachter, W. Chem. Ber. 1892, 25, 2632. Willgerodt, C. "Die Organischen Verbindungen mit Mehrwertigen Jod"; Enke: Stuttgart, 1914; p 134. Banks, D. E. Chem. Reo. 1966, 66, 243 (see especially p 255). (b) Baker, G. P.; Mann, F. G. Sheppard, N.; Tetlow, A. J. J . Chem. SOC.1965, 3721. X-ray structure: Shefter, E.; Wolf, W. J . Pharm. Sci. 1965, 5 4 , 104; Nature ondo don) 1964, 203, 512.
0 1984 American Chemical Society
2652 J . Am. Chem. Soc.. Vol. 106, No. 9, 1984
Moss, Alwis, and Shin
Table I. Iodosobenzoate and Iodo\ybenzoate Cleavages in Micellar CTACIa case
catalyst
substra tc
1O2kbmmax, 5'.
104k0. s-'
kGmax/k0
51.4 72.3 29.9 44.4 343 97.4 394 3440 1800 ____a Kjnctic data are taken from Table\ I-V of the supplementary material. Conditions: 0.02 M phosphate buffer, pH 8.0, p = 0.08 (NaCI). 0.645 vel% DMI , 0.645 v o l 7 CH,CN, 25 * 0.5 "C. [substrate] = 1.0 X 10.' M, [catalyst] = 1.0 X M (cases 1-6) or 7.14 x IO" M (cases 7-9). k;, max values are frotn Tables I-V of t h e supplementrlry material. Reproducibilities are