3310 NOTES 1-indanonelo in 400 ml of dry chloroform was refluxed for 1.5 hr. After removal of the solvent in vacuo, the solid product was recrystallized from chloroform-hexane to give 42.0 g (66.3%) of 4, mp 130-131", as a yellow solid: ir, 5.88 (C=O), 6.28 (phenyl), 6.65, and 7.52 /I (NOz). Anal. Calcd for CI5Hl1NOaS: C, 63.16; H, 3.89. Found: C, 63.32; H , 3.73. Ja,d-Dihydroindeno [2,l-b]-1,4-benzothiazine (6).-To a boiling solution of 56.4 g (0.198 mol) of 4 in 500 ml of glacial acetic acid was slowly added with stirring a hot solution of 140 g (0.521 mol) of stannous chloride dihydrate in 150 ml of concentrated hydrochloric acid. After the addition was completed (about 15 min), the solution was boiled an additional 30 min before cooling. The golden yellow solid which had crystallized was washed with 95% ethanol followed by ether, then dried to give 64.0 g (80.1%) of bis(5a,6-dihydroindeno [2,l-b]-1,4-benzothiazinium) hexachlorostannate (S), mp 170" dec. As 5 was only sparingly soluble in water and organic solvents, it was not further purified but used directly in the next step: ir, Y 6.12 p (C=N). A mixture of 30.4 g (0.0376 mol) of 5 in 500 ml of 10% sodium hydroxide solution was shaken intermittently for 1 hr. The yellow-tan solid which formed was washed with dilute sodium hydroxide until free of' tin salts, then with water until free of base. After drying, 16.8 g (94.27,) of 6 was obtained as a light tan solid. Recrystallization of a small portion of this solid from chloroform gave pure 6: mp 100-105° dec; ir, 3.30 and 3.52 (C-H), 6.12 p (C=N). Anal. Calcd for Cl&NS: C, 75.93; H, 4.67. Found: C, 75.56; H , 4.81. 6-Bromoindeno [2,1-b]-1,4-benzothiazine (7).-To a solution of 16.0 g (0.0675 mol) of 6 in 200 ml of carbon tetrachloride was added slowly with swirling a solution of 21.6 g (0.135 mol) of bromine in 50 ml of carbon tetrachloride. A brown precipitate formed initially, but after one-third of the bromine was added, the mixture turned dark green. Hydrogen bromide evolution did not begin until over ha1:f of the bromine was added. The mixture was warmed and allowed to stand overnight at room temperature. The dark green solid (hydrobromide of 7) which had precipitated was dried and added t'o 500 ml of 10% sodium hydroxide. After intermittent shaking for 1 hr, a deep purple solid formed. This was washed with water and dried to give 18.0 g (84.8y0) of 7, mp 205-206'. Compound 7 was soluble in concentrated hydrochloric acid, giving a green solution: ir, 3.37 (C-H), 6.26, 6.58, 7.01, 8.01, 8.17, 10.60, 13.1 (broad), and 13.3 p (broad). The analytical sample was purified by sublimation, mp 205-206'. Anal. Calcd for C15H8BrNS: C, 57.34; H, 2.57; N , 4.46. Found: C, 57.12; H, :2.59; N, 4.18. The hydrobromide of 7 had mp 155" dec. Anal. Calcd for CljH9Br2NS: C, 45.57; H, 2.28; N, 3.54. Found: C, 45.58; H , :2.33; N, 3.28. Nucleophilic Substitution Reactions of 7. A. 6-Phenylthioindeno[2,1-b]-1,4-benzothiazine (Sa).-A solution of sodium thiophenoxide was prepared by adding a solution of 0.36 g (3.3 mmol) of thiophenol in 5 ml of absolute ethanol to a solution of 0.18 g (3.3 mmol) of sodium met,hoxide in 10 ml of absolute ethanol. To this solution was added a solution of 1.0 g (3.2 mmol) of 7 in 10 ml of absolute ethanol, and the mixture was refluxed overnight under nitrogen. Water was added to the cooled mixture t o precipitate a purple solid, which was recrystallized from ethanol-water to give 0.8 g (737,) of Sa: mp 114-116"; ir, 3.38 (C-H), 6.26, 6.36, 6.68, 6.81, 6.88, 7.01, 7.68, 8.01, 8.17, 13.4 (very broad), and 14.58 p ; mass spectrum (low ionizing voltage), 343. Anal. Calcd for CnlHI3NS2: C, 73.46; H, 3.82; N, 4.08. Found: C, 73.21; H, 3.85; N, 4.19. B. 6-Cyanoindeno[2,l-b] -1,4-benzothiazine (Sb).-A mixture of 1.0 g (3.2 mmol) of 7, 0.35 g (3.9 mmol) of cuprous cyanide, and 10 ml of dirnethylformamide was refluxed for 4 hr.* After cooling, the mixture was poured into a ferric chloride-hydrochloric acid solution and warmed for 30 min. The precipitated solid was washed successively with dilute hydrochloric acid, dilute sodium hydroxide, and water, then dried to give 0.8 g (96%) of Sb, mp 215-220", as a deep purple solid: ir, 3.43 (C-H), 4.63 (CEN), 6.29, 6.68, 6.92, 7.06, 7.68, 7.93, 8.12, 8.99, 13.1 (broad), and 13.3 p (broad); mass spectrum, 260. The analytical sample was purified by :sublimation, mp 215-220'. (10) K. L. Rinehart, Jr., and D. H. Gustafson, J . Org. Chem., 26, 1836 (1960).
The Journal of Organic Chemistry Anal. Calcd for CleHsNzS: C, 73.84; H, 3.10; N, 10.77. Found: C, 74.18; H, 3.17; N, 10.93. C. 6-0xo-5a,6-dihydroindeno[2,l-b]-l,4-benzothiazine (9).A solution of 1.0 g (3.2 mmol) of 7 in 30 ml (303 mmol) of piperidine was refluxed under nitrogen for 5 days. The excess piperidine was removed in v a m and the residue was taken up in ether. The precipitated piperidinium bromide was removed by filtration (recovered 0.4 g, 75% of theoretical). The ethereal filtrate was extracted with dilute hydrochloric acid to give a blue aqueous solution. The purple ether layer containing unreacted 7 was discarded. The aqueous acidic solution was extracted with ether until all unreacted 7 was removed. When the solution was made basic with dilute sodium hydroxide, a deep blue solution was obtained, from which no organic material could be extracted with ether. However, when the solution was carefully neutralized by adding dilute hydrochloric acid, a greenish blue substance precipitated, which was extracted with ether. The ether solution was washed with water and dried over anhydrous sodium sulfate, and the ether was removed in vacuo. Recrystallization of the residue from ether-ethanol gave 0.2 g (25%) of 9 , mp 210-212', as a blue-green solid. Compound 9 waa readily soluble in dilute acid, giving a blue solution, and in dilute base, giving a deep blue solution: ir, 3.24 and 3.43 (C-H), 5.91 (C=O), 6.10 (C=N), 6.27, 6.35, 6.61, 6.83, 7.02, 7.32, 7.78, 8.26, 11.7, and 13.5 p. Anal. Calcd for ClsHgNOS: C, 71.71; H, 3.61; N, 5.57. Found: C, 71.97; H, 3.71; N, 5.67. Indeno[2,l-b]-l,4-benzothiazinyl-6-carboxylicAcid (&).-A mixture of 0.50 g (1.9 mmol) of Sb in 15 ml of glacial acetic acid, 15 ml of concentrated hydrochloric acid, and 5 ml of water was refluxed for 4 hr. The solvents were removed in vacuo and the residue was taken up in ether. The ether solution was extracted with dilute hydroxide until the extracts were colorless. The ether solution containing unreacted Sb was discarded. The combined basic extracts were acidified with dilute hydrochloric acid, and the product was extracted with ether. After the ether washing layer was washed with water and dried over anhydrous sodium sulfate, the ether was removed in vacuo to give less than 0.1 g of&, mp >250°, as a dark purple solid. Compound 8c was soluble in dilute base: ir, 3.3-3.7 (COOH), 6.07 (conjugated C==O), 6.64, 6.85, 7.04, 7.63, 7.98, 8.13, 13.12, and 13.44 p. Anal. Calcd for C1eHgN02S: N, 5.02. Found: N , 4.82.
Registry N o . 4 , 16888-88-3; 6 , 16888-89-4; 7, 16888-90-7; 7 HBr, 16888-91-8; 8a, 16888-92-9; 8b, 16888-93-0; 8c, 16888-94-1; 9, 16888-95-2.
Acknowledgment.-This investigation was supported by Public Health Research Grant No. CA-07351 from the National Cancer Institute.
Tishchenko Reaction of Chloral by Aluminum Haloalcoholates TAKEO SAEGUSA AND TAKASHI UESHIM.4 Department of Synthetic Chemistry, Faculty of Engineering, Kyoto University, Kyoto, Japan Received February 9, 1968
The Tishchenko reaction of trichloroacetaldehyde (chloral) by the usual aluminum alcoholate catalyst is very sluggish.l - 2 In this communication, we report our finding that some aluminum haloalcoholates cause a rapid Tishchenko reaction of chloral t o produce trichloroethyl trichloroacetate. The results are sumClaCCHO +ClaCCOOCH2CCla (1) 1. Lin and A. R. Day, J . Amer. Chem. Soc., 74, 5133 (1952). (2) R. Dworsak, Monatsch., 47, 11 (1927).
(1)
VoZ. $3, No. 8, August 1968
NOTES 3311
marized in Table I. The catalyst activity is expressed in two ways, the reaction time (minutes) required for 30% conversion and the conversion per cent after 1 hr of reaction. The results clearly demonstrate that Al(0CH2CCl& (I), A1(OCH2CBr3)2(11), and Al[OCH(CH2C12)2]3(111) as well as alkylaluminum compounds are distinguished by high catalyst activity among aluminum compound catalysts in the Tishchenko reaction of chloral. Al(OCH2CHC12)3and Al(OCH2CH2c1)3 are also aluminum haloalcoholates, but they are less active. The high catalytic activity of I1 has also been observed in the Tishchenko reaction of tribromoacetaldehyde (bromal). The characteristic activities of I, 11, and I11 in the Tishchenko reactions may be due, at least partly, to their marked tendencies of dissociation into monomeric form in the presence of donors such as carbonyl compounds (eq 2). [Al(OR)s]n f
nD
4
nlz>AI
