We have synthesized [Pt(CN-iso-C 3 H 7 ) 4 ][M(CN) 4 ] (M ) Pt, Pd) and studied their reversible hydration and sorption properties with UV-vis, FT-IR spectroscopy, and X-ray diffraction. Powder diffraction studies show that anhydrous [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] and [Pt(CN-iso-C 3 H 7 ) 4 ][Pd(CN) 4 ] crystallize in a tetragonal space group with nearly identical lattice constants. Gravimetric studies reveal that variable guest-host stoichiometries occur when solid [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] sorbs the guest at room temperature from the gas phase [water, 12.1(1) molecules per formula unit, chloroform 6.0(1), methanol 8.0(1), and trifluoroethanol 4.1(1)]; these sorption processes are reversible. The unit cell distances in the tetragonal ab-plane expand dramatically when the solvent guests are sorbed, but changes along the c-axis (the M-M direction) are minimal. Crystallization of [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ] from water gives monoclinic crystals of a hexadecahydrate [Pt(CN-iso-C 3 H 7 ) 4 ][Pt(CN) 4 ]‚16H 2 O. This salt consists of alternating cation/anion chains along b with an average Pt-Pt distance of b/2 ) 3.1521(1) Å. The sixteen water molecules per formula weight interlace neighboring chains via H-bonding with each other and the CNions of the Pt(CN) 4 2units. The shifts in the UV-vis and IR spectra that occur when solvent guests are sorbed by the double complex salts are discussed in terms of the lattice expansions that are observed. A mechanism for the lattice expansions that accompany the sorption of guest molecules is proposed.
COP-Cl catalyzes the rearrangement of (E)-allylic trichloroacetimidates to provide transposed allylic trichloroacetamides of high enantiopurity, a transformation that underlies the first truly practical method for transforming prochiral allylic alcohols to enantioenriched allylic amines and congeners. The high functional group compatibility of this asymmetric rearrangement and the demonstrated broad utility in synthesis of the allylic trichloroacetimidate to allylic trichloroacetamide conversion are singular features of this new catalytic asymmetric reaction.
Palladium(II) catalysts based on a ferrocenyloxazoline palladacyclic (FOP) scaffold were synthesized and evaluated for the rearrangement of prochiral allylic N-(4-methoxyphenyl)benzimidates. When iodide-bridged dimer FOP precatalysts are activated by reaction with excess silver trifluoroacetate, the allylic rearrangement of both E and Z prochiral primary allylic N-(4-methoxyphenyl)benzimidates takes place at room temperature to give the corresponding chiral allylic N-(4-methoxyphenyl)benzamides in high yield and good ee (typically 81-95%). Several allylic imidate motifs were evaluated also. Because the corresponding enantioenriched allylic amide products can be deprotected in good yield to give enantioenriched allylic amines, allylic N-aryltrifluoroacetimidates were identified as promising substrates.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.