As reações de crotonaldeído (8) com tiofenol (2) e benzalacetona (10) com 1,2-etanoditiol (11) levam aos produtos de adição de Michael. As reações de tiofenol (2) com (R)-carvona (13) e (S)-perilaldeído (15) levam aos produtos (2S,3R,5S)-5-isopropenil-2-metil-3-feniltio-cicloexanona (14) e (1R,2R,4S)-4-isopropenil-2-feniltio-cicloexano carbaldeído (16), respectivamente. Também é apresentada a elucidação inequívoca da estereoquímica de 14 e 16 por RMN.

The reactions of crotonaldehyde (8) with thiophenol (2) and benzalacetone (10) with ethane-1,2-dithiol (11) yield Michael addition products. The reactions of thiophenol (2) with (R)-carvone (13) and (S)-perillaldehyde (15) lead to (2S,3R,5S)-5-isopropenyl-2-methyl-3-(phenylthio)cyclohexanone (14) and (1R,2R,4S)-4-isopropenyl-2-(phenylthio)cyclohexanecarbaldehyde (16), respectively. An unambiguous elucidation of the stereochemistry of 14 and 16 by NMR is also presented.

The world is in a process of awakening with respect to the environment. Our society has started to recognize that the environment is one of our largest resources and has begun legally enforce its protection. In Brazil, the environmental law is constitutionally guaranteed. International treaties have been signed, amongst them the Agenda 21 which is a commitment to sustainable development. Green Chemistry is a strategy that helps make this commitment. The literature presents many examples of studies of the application of Green Chemistry philosophy. In this paper we will present some points that we believe to be important and promising.

The use of water as solvent in organic reactions has been uncommon for several reasons, among them the low solubility of the reactants, the incompatibility of the intermediates with water, and the competition between the desired reaction and hydrolysis. Breslow in 1980, demonstrated that the hydrophobic effect accelerates Diels-Alder reactions and gives a high endo/exo selectivity. Since then, many other reactions were studied in this medium, and below we show the principal results. Besides the academic interest, human and economic aspects are included in this study. Water as a solvent minimizes environmental impact, costs and increases operational safety.

A review on the electrophilic addition of iodine to alkenes in the presence of oxygen containing nucleophiles (cohalogenation reaction) is presented. The intermolecular reactions are discussed with emphasis in methods of reaction and synthetic applications of the resulting vicinal iodo-functionalized products (iodohydrins, beta-iodoethers and beta-iodocarboxylates).