Publications by authors named "C Dolka"

Arsenic, cadmium and lead levels in tobacco filler and cigarette smoke were determined in a 568-sample worldwide survey. Median tobacco levels for arsenic, cadmium and lead were 237, 769 and 397 ng/g respectively, comparable to those previously reported albeit somewhat lower for lead and cadmium. Median mainstream smoke yields for arsenic, cadmium and lead were <3.

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Cigarettes with menthol capsules embedded in the filter have been introduced recently in many countries. At the same time, concerns have been expressed that filter performance could be affected by the crushing of the capsule therein, altering mainstream smoke constituent yields, ultimately with the potential to impact the toxicity of these products. The present study investigates the possible mechanisms underlying differences in smoke constituent deliveries following the crushing of a menthol capsule in a cigarette filter.

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The Cu-free asymmetric allylic alkylation, catalysed by NHC, with Grignard reagents is reported on allyl bromide derivatives with good results. The enantioselectivity was quite homogeneous (around 85% ee) on large and various substrates, regardless of the nature of the Grignard reagent. The formation of stereogenic quaternary centres was highly regioselective for both aliphatic and aromatic derivatives with good enantiomeric excess (up to 92% ee).

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Several novel 1,1-disubstituted-8-hydroxynaphthalen-2(1H)-ones have been efficiently synthesized via a two-step sequence from 2-hydroxy-1-naphthaldehyde oxime. The methodology involves oxidative ring closure and alkoxylation to 3a-alkoxynaphtho[1,8-de][1,2]oxazin-4(3aH)-ones, followed by thermal ring-opening. Both thermal and microwave irradiation conditions were used.

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