Section 2.4.6 Spectacular results were reported by Mukaiyama and coworkers167,168 in the field of chiral Lewis acids. Reaction of thiol ester derived silylketene acetals with aldehydes promoted by the combined use of a chiral diamine coordinated with tin(II) triflate and tributyltin fluoride gave...
Starting from organochlorosilanes the reaction with a thiol in the presence of a Lewis base like triethyl amine or pyridine yields organomercaptosilanes [1]: 2 py Ph2SiCI2 + 2 PhSH Phi;Si(SPh)2 (1) - 2 pyHCI The thiol can also be transformed into its lithiumaluminium or lead salt pri...
Pd-catalyzed coupling reactions have also been used for the preparation of Lewis acid organoboron polymers, which are exciting candidates in materials science due to their coordination behavior.309 5.12.3.7.3 Atom transfer radical addition Alkyl halides as side chain functional groups have been employed...
Die hohe Acidität der SH-Funktion von 4 verhinderte, in Gegenwart von Lewis-Basen wie Phos- phinen thermisch oder photolytisch aus 4 CO abzuspalten und durch andere Liganden zu ersetzen. Die Photolyse von 4 in Abwesenheit solcher Liganden L lieferte nur nicht näher ...
Polybutenes produced in the presence of a Lewis acid such as an aluminum chloride catalyst can be considered to be mono-olefins in which the olefin or double bound structure is primarily of the trisubstituted and tetrasubstituted types. When such polybutenes are epoxidized, the resulting epoxide ...
Preparation of Sialyl-Lewisx (SLX)-PEG-DSPE. The bromacetylated derivative of SLX22 (98 mg, 0.08 mmol) is added to a DMF (2.8 ml) solution of HS-PEG-DSPE (197 mg, 0.07 mmol) followed by potassium iodide (14.3 mg, 0.086 mmol). After approximately 5 min, a NaHCO3 (0.4 M)/Na2EDT...
Scheme 1. Synthesis and molecular structure of the Λ isomer of 2a’ (cis-α configuration). Methyl groups of the tert-butyl groups have been omitted. Sign in to download hi-res image Scheme 2. Synthesis and molecular structure of 2b(cis-β) and 3b(cis-α, Λ configuration). Methyl gro...