0000000000099333
AUTHOR
L. Lamartina
Studies in organic mass spectrometry. Part 25. Benzyl ion formation in chemical ionisation (methane or isobutane) of some ortho-alkylhetero-substituted diphenylcarbinols
The behaviour of some ortho-alkylhetero-substituted diphenylcarbinols, including deuterium labelled derivatives, under chemical ionisation (methane or isobutane) conditions has been investigated. It has been determined that ortho-alkylhetero diphenylmethyl cations formed by water elimination from the protonated molecule undergo consecutive rearrangements which afford benzyl (or tropylium) ions previously observed for ortho- substituted diphenylcarbenium ions generated by electron ionisation. This reaction also occurs under low-energy collision conditions. Copyright (C) 2000 John Wiley and Sons, Ltd.
Bonandiol: A new, irregular, monocyclic diterpene from (L.) Halacsy (umbelliferae)
A new, irregular, monocyclic diterpene, bonandiol (1), has been isolated from Bonannia graeca. The structure of bonandiol has been deduced from spectral data and chemical evidence.
Crystal and molecular structure of 2,3,6,7-tetramethoxy-9-trichloromethyl-10-carboxymethyl-9,10-dihydroanthracene
Cl3O6C21H21,Mr=475.75, orthorhombic,P212121,a=21.895(3),b=12.101(2), andc=8.237(2) A,V=2182.4(7) A3,Dx=1.45 g cm−3 forZ=4, λ(MoKα)=0.71069 Aμ=3.99 cm−1,F(000) 984, room temperature,R=0.035 for 1877 observed reflections. The molecule exhibits a folded conformation: the dihedral angle between the benzene rings is 28.3(1)°. The central ring is characterized by acis diaxal configuration of hydrogen atoms in the 9, 10 positions, confirming the 13-C NMR results.