Polar bromination and chlorination of cyclopropane

Liquid crystals based on hypervalent sulfur fluorides

“…Reducing agents such as tri-n-butyl tin hydride [20], NaBH 4 [21] and magnesium [22] showed no reactivity at all. The use of zinc [23] and LiAlH 4 [24] resulted only in the reduction of the SF 5 group. n-Butyl lithium [22] acted only as a base but did not cause bromine lithium exchange.…”

Torsional vibrational structure of the propene radical cation studied by high-resolution photoelectron spectroscopy

“…The partially deuterated isotopomers were synthesized following instructions found in the literature [34][35][36] and purified to a level of better than 99% as determined by high-pressure liquid chromatography. The identity of the isotopomers was verified by time-of-flight mass spectrometry and photoionization spectroscopy (see gray traces in Fig.…”

ChemInform Abstract: Rogiolenyne A, B, and C: The First Branched Marine C15 Acetogenins. Isolation from the Red Seaweed Laurencia microcladia or the Sponge Spongia zimocca of Il Rogiolo.

“…1 ) ; H-C(11) is coupled not only to H-C(I0) and H-C(12) but also to the two diastereotopic protons at C (15) which are deshielded by the Br-atom (S(H) = 3.58 and 3.38 ppm) and coupled to the C-atom at 30.47 ppm (t). The Cl-C(6) group which is indicated by the MS fragment [M -C6H6C1]+ is part of the CH(6) (C1)-CH(7)(0) portion, as indicated by the coupling ( ' J ) of H-C(6) and H-C (7) to the deshielded C-atoms at 63.42 and 73.72 ppm (d), respectively3). The d's at 53.17 and 55.93 ppm for C (9) and C(10) are compatible with an epoxide group, while the d at 74.82 ppm indicates 0-bridging at C(12).…”

“…The d's at 53.17 and 55.93 ppm for C (9) and C(10) are compatible with an epoxide group, while the d at 74.82 ppm indicates 0-bridging at C(12). A trans-diaxial coupling of H-C (7) and Hb-C(8) supports the p-position for the chain at C (7), while a positive NOE for Hb-C(8)/H-C(12) indicates the a-position for the Et group at C(12)4), and a small coupling between H-C(I1) and H-C(12) supports the a-position for the CH,Br group. Characteristic values for 3(3,4) (10.9 Hz) and S(H-C(I)) (3.13 ppm) indicate the (Z)-configuration at C(3)=C(4).…”

“…For the alternativeeight-membered cyclic structure with a C, linear sidechain and C1 at C (7), the resonance of C(7) would be expected at higher field rather than that of C (6). The signals of (-)-1 of C (7) and C(12) of (-)-11 appear ca. 5 ppm upfield when compared to oxepanes with &-arrangement of the substituents at C (7) and C(12) [1] [2].…”