ABSTRACT
Across a range of recent terrorist attacks in the United Kingdom, the question of how crowds behave in confined public space is an important concern. Classical theoretical assumptions are that human behaviour in such contexts is relatively uniform, self-interested and pathological. We contest these assumptions by reporting on a study of public response to a marauding knife attack that occurred on London's underground rail network in 2015. The analysis draws primarily upon footage from 27 CCTV cameras positioned across the station footprint supplemented by social media, news footage, radio logs and incident reports. Using an innovative methodology, we topographically and chronologically mapped behaviours during the incident. The analysis demonstrates that while rapid egressions occurred as the threat escalated, at every phase of the incident members of the public intervened spontaneously with coordinated, purposeful, socially oriented actions. This behavioural pattern contrasts with classical assumptions of a chaotic and apathetic crowd in emergencies. We highlight eight complementary categories of actions in the public response that appeared functional for the collective safety of the crowd during the short period before the police arrived. The policy implications for emergency planning, and the methodological innovations involving the use of video data are discussed.
Subject(s)
Terrorism , Humans , London , Social Behavior , Police , United KingdomABSTRACT
Chiral ferrocenyl heterobidentate P/S ligands bearing both central and planar chirality were prepared from (S)-Ugi's amine via a three-step modular synthesis. Through systematic screening and optimization, L8 was found to be the best ligand for Pd-catalyzed asymmetric allylic alkylation of indoles with ee's up to 96% being attained.
ABSTRACT
A new chiral tertiary aminonaphthol ligand 3b served as a highly efficient ligand for the asymmetric catalytic phenyl transfer to aromatic aldehydes and a variety of chiral diarylmethanols was prepared in high ee values (ee up to 99%) and chemical yields. The straightforward syntheses of both 3b and its enantiomer provide an excellent opportunity for large-scale applications.
ABSTRACT
Essentially complete atropdiastereoselectivity was realized in the preparation of biaryl diphosphine dioxide by asymmetric intramolecular Ullmann coupling and oxidative coupling with central-to-axial chirality transfer. A bridged C(2)-symmetric biphenyl phosphine ligand possessing additional chiral centers on the linking unit of the biphenyl groups was synthesized. No resolution step was required for the preparation of the enantiomerically pure chiral ligand. These findings offer a general and practical tool for the development of previously uninvestigated atropdiastereomeric biaryl phosphine ligands. The diphosphine ligand was found to be highly effective in the asymmetric hydrogenation of alpha- and beta-ketoesters, 2-(6'-methoxy-2'-naphthyl)propenoic acid, beta-(acylamino)acrylates, and enol acetates.
ABSTRACT
[formula: see text] High enantioselectivities have been achieved in the 1,4-addition of dialkylzincs to 2-cyclopentenone, 2-cyclohexenone, and 2-cycloheptenone with ee values up to 99% by using chiral aryl diphosphite ligands derived from H8-binaphthol.