Addition reactions of the uniparticulate electrophile chlorosulfonyl isocyanate to highly strained bicyclic hydrocarbons

Abstract

The addition of chlorosulfonyl isocyanate to a variety of bicyclo[1.1.0]butanes and to bicyclo[2.1.01-

2‐Azabicyclo [3.2.0] Heptane‐3‐One

“…The spectral data published [1,2] for (II) closely corresponds to that obtained for (I). Mixed melting point determination [3a] and direct comparison of the 100 MHz NMR spectra [3a] of compounds (I) and (II) established the identity of the two specimens.…”

Unsaturated heterocyclic systems. XCIV. Response of homo- and benzhomobarrelenes to uniparticulate electrophilic attack. Effect of a lateral cyclopropane ring on the direction and stereochemistry of chlorosulfonyl isocyanate addition

“…Adjustment to pH 1 and final extraction afforded 1.0 g (80% based upon estimate of 4 originally present) of maleic acid-2,3-di, mp 132-134.5°. Recrystallization from ether with charcoal decolorization gave pure product, mp 137-138°. TricyclotS^^.O^jnona-e,8-diene-6,Z-dz (6). A mixture of maleic acid-2,S-d2 (640 mg, 5.42 mmol), 10.0 g (0.108 mol) of distilled cycloheptatriene, and 10 ml of xylene was carefully heated to reflux (foaming!)…”

“…The first substance to elute proved to be lactone 7 (14 mg, 2.3%), which was obtained as white crystals, mp 88.5-89.5°, after sublimation (50°, 0.02 mm) and recrystallization from ether-pentane: vm&x (CHC13) 1775 cm"1; áMe4Si (CDC13) 4.55-4.75 (m, 1, >CHO-), 2.85-2.98 (m, 1, >CHCO-), 2.52-2.79 (m, 1, bridgehead), 1.60-2.20 (m, 3, tertiary cyclopropyls), 0.77-1.52 (m, 2, tertiary cyclopropyls), 0.46-0.72 (m, 1, anti secondary cyclopropyl), and 0.12 to -0.17 (m, The second substance isolated was /3-lactam 8 (20 mg, 3.2%), white crystals, mp 150-151°, after sublimation (80°, 0.02 mm) and recrystallization from ether: vmax (CHCI3) 3250 and 1747 cm-1; 5Me4Si (CDCI3) 6.33 (br s, 1, >NH), 5.77-6.05 (m, 2, olefinic), 3.44-3.68 (m, 1, >CHN<), 2.85-3.23 (m, 3, >CHCOand bridgeheads), 0.77-1.42 (m, 2, tertiary cyclopropyls), and 0.02-0.33 (m, 2, secondary cyclopropyls); m/e (caled) 161.0841, (obsd) 161.0843.…”

Catalysis Within the Self-Assembled Resorcin[4]arene Hexamer

“…Isonitriles are a special class of molecules [49], characterized by an extremely repellent odor, where the R─N≡C functional group can be described with either the zwitterionic form with positive N and negative C, or the predominantly carbenic electron-poor structure [50] that overall confer a linear geometry to the NC bond. Because of its electronic structure, isonitriles are largely investigated in multicomponent reactions, since the C atom of the isonitrile moiety reacts either as an electrophile [51] or as a nucleophile [52].…”