Synthesis of substituted hydroazulenes

Abstract

Scheme IV Mn(II) + S Mn(II)-S (17) Cr(VI) + 3Mn(II)-S ^±. Cr(III) + 3Mn(III)-S (18) Mn(III)-S Mn(II) + P (19)However, in our study chromium(III) definitely did not exhibit any influence on the reaction rate. Therefore, any mechanism which would require an equilibrium involving chromium(III) to be established prior to the rate-limiting step of the oxidation has to be rejected, and we therefore cannot apply the mechanism proposed by Kemp and Waters to rationalize our results. Further, while the formation of a complex between manganese and an -hydroxy acid was an entirely plausible assumption, it would be much less justified to propose the formation of an intermediate complex in the case of the oxidation of cyclobutanol.

Metal-assisted carbon-carbon (C-C) bond formation. Use of a methyl vinyl ketone complex in Michael condensations

“…(18) Maximum yield is obtained after 15 min at -20°( cis, 55%; trans, 21%) but drops if the reaction is quenched after 30 min at 0°( cis, 14%; trans, 13%). ( 19) The extent of deuterium incorporation was determined by NMR spectral analysis, using integration of the signal appearing at 5.90 (d, a H, J = 13 Hz, cis isomer), and 6.38 (d, a H, J = 16 Hz, trans isomer). Cf., K.…”

Alkylation of enolate ions generated regiospecifically via organocopper reactions. Synthesis of decalin sesquiterpene valerane and of prostaglandin model systems

“…Trimethylsilyl (6-Methyl-l-cyclohexen-l-ol) Ether (5). To a stirred suspension of 970 mg (5.1 mmol) of cuprous iodide in 12 ml of diethyl ether at 0°was added 5.7 ml of 1.76 (10.0 mmol) methyllithium.…”

“…The trans-2,3-substitution pattern was determined utilizing a combination of nmr shift reagent58 and spin-spin decoupling. When 75 mg of Eu(fod)3 ("Resolve-Al") was added to 30 mg of 3-ethyl-2-propylcyclopentanone in 0.5 ml of CDC13, the following nmr spectrum resulted: 0.90 (s, shift reagent), 1.4-1.6 (pair of overlapping t, J = 7 Hz, 6 H, methyl groups), 2.3 (m, protons of n-propyl chain), 2.5-3.6 (m, cyclopentyl and ethyl protons), 3.9 (m, 2 H, methylene of propyl group adjacent to ring), 5.6 (m, 1 H, -methine proton), 5.9 (m, 2 H, -methylene protons). When the signal at 3.80 was irradiated, the signal for the -methine proton was resolved into a doublet, 7 = 11 Hz.…”

“…D is 2,5-(or 2,2-) di-n-butyl-3-vinylcyclopentanone (26, 50 mg, 22%) isolated via preparative glpc (column E, 200°, 40 min): nmr (CC14) 5.8 (m, 1 ), 5.04 (m, 2 ), 1.1-2.9 (m, 17 ), 0.84 (m, 6 H); ir (CCI4) 1738 cm-1 (C=0); mass spectrum (70 eV) m/e 222 (molecular ion), 179, 166, 137, 109, 55. Anal.…”