Use of a bulky bidentate bis(NHC) ligand allows isolation of a stable cationic methylpalladium carbonyl complex that undergoes clean carbonylation to an acyl complex under excess CO, modeling a key step in CO/alkene copolymerization.

Recent developments in sensor technology have given an onset for studying the earth surface features based on the detailed spectroscopic observation of different rocks and minerals. The spectroscopic profiles of the rocks are always quite different than their constituent minerals however, the spectral profile of a rock can be broadly reconstituted from the spectral profile of each constituent minerals. Interpretation of rock spectra using the spectra of constituent minerals based on relative spectral matching can bring out interesting information on the rock. Present study is an effort toward this and it highlights how visible-near infrared-shortwave-infrared (VNIR-SWIR) rock spectroscopy acts as an useful tool for understanding the rock-mineralogy in indirect and rapid way. It has also been observed that spectral signatures of rocks; studied in present case, are related to spectral signatures of constituent minerals although absorption features of constituent mineral in the rock are also modified by the other minerals juxtaposed in the rock fabric. However, each rock of the study area has their significant absorption features, but many of the absorption signatures are closely spaced, as altered rock has significant absorption at 2305 nm whereas amphibolite has its important absorption signature in 2385 nm and metabasalt has its significant absorption at 2342 nm. Therefore spectral measurement of high spectral resolution with appreciable signal to noise ratio (SNR) only can detect rocks from each other based on the absorption signatures mentioned above (each of which is 10 to 20 nm apart from the other) and therefore spectroscopy of rock is an innovative technique to map rocks and minerals based on the spectral signatures.

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Simple silver salts and dicationic palladium bis(N-heterocyclic carbene) complexes were found to be effective and complementary catalysts for Nazarov cyclizations of divinyl β-keto esters. A sterically hindered palladium bis(NHC) catalyst provided remarkable endo:exo selectivity in cyclizations of cyclohexenyl β-keto esters, whereas AgSbF6 gave improved yields with electron-deficient substrates. The high activities observed with silver salts are significant, given their widespread use as additives in catalytic Nazarov reactions.