Of the six structures presented here, five involve clearly defined hydrophilic layers built up from classical hydrogen bonding systems. Of three solvent-free structures, 2,4and 3,5-dichloroanilinium chlorides both form ribbon structures involving annelated R4(8) rings with NH2 donors (two hydrogen atoms from the positively charged NH3 groups) and chloride acceptors. The ribbons are linked by we...

Hydrolyses of acid derivatives (e.g., carboxylic acid chlorides and fluorides, fluoro- and chloroformates, sulfonyl chlorides, phosphorochloridates, anhydrides) exhibit pseudo-first order kinetics. Reaction mechanisms vary from those involving a cationic intermediate (SN1) to concerted SN2 processes, and further to third order reactions, in which one solvent molecule acts as the attacking nucle...

The Pd-catalyzed intramolecular addition of carbamoyl chlorides and aryl halides across alkynes is investigated by means of DFT calculations and mechanistic test experiments. The data suggest a mechanistic pathway that involves oxidative addition, alkyne insertion, cis / trans isomerization and reductive elimination. Our data indicate that oxidative addition is the reactivity limiting step in t...

G e o r g e S o s n o v s k y a n d J a m e s A . K r o g h Department of Chemistry, University o f Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, U S A Z. Naturforsch. 84b , 511-515 (1979); received N o v e m b e r 28, 1978 Sulfur Chlorides and Disulfides, Conversion o f Aldehydes to Nitriles, Selenium Chlorides and Diselenides, Nitriles, A ldox imes The comparat ive usefulness of six sulfur...