Alkoxymethyl complexes

Nelson has similarly shown76 that the neutral hydroxymethyl complex, [Ru(C0)2(CH20H)(Ti5-Cp )], is formed by reduction of [Ru(CO)3( n5-Cp )][BF4] with a three-fold excess of Na[BH3CN] in methanol. The reaction of the starting material with an equimolar quantity of NafBHsCN] in methanol yields the alkoxymethyl complex, [Ru(C0)2(CH20Me)(Ti5-Cp )], as the major... 

The spectroscopically characterized iron methylene complex 63 is formed in a closely related reaction of an alkoxymethyl compound (92) ... 

We have delineated viable coordinated ligand reactions and their attendant intermediates for the stoichiometric conversion of CO ligands selectively to the C2 organics ethane, ethylene, methyl (or ethyl) acetate, and acetaldehyde. We now outline results from three lines of research (1) T -Alkoxymethyl iron complexes CpFe(C0)2CH20R (2) are available by reducing coordinated CO on CpFe(C0)3+ (1) [Cp = r -CsHs]. Compounds 2 then form t -alkoxyacetyl complexes via migratory-insertion (i,e. CO... 

We have demonstrated that NaBH3CN in alcohol reduces a CO ligand on CpFe(CO)3+ and generates an alkoxymethyl iron complex. Versatile alkoxyacetyl complexes CpFe(C0)L(C0CH20R)... 

Without question, the most important developments in this field over the past 10 years have been in the area of enantioselective hydroborations. New chiral catalyst systems are typically tested in hydroborations of vinyl arenes, as reactions using HBcat and a cationic rhodium catalyst are well known to give selective formation of the unusual branched isomer. In related studies, enantiopure 2,2-disubstituted cyclopropyl boronates were easily prepared via the catalytic asymmetric hydroboration of 3,3-disubstituted cyclopropenes using a number of chiral neutral rhodium complexes (equation 13). Directing groups, such as esters and alkoxymethyl substituents, were necessary for achieving... 

Appropriate alkyl iodides or bromides were reacted with 57 and 2-epi-Sl in the presence of Ag20 in CH3CN with yields ranging from 36 to 77% (74, Scheme 10) [34, 51]. However, with these conditions preparation of branched alkyl ethers was unsuccessful [51]. Reacting 57 with chloromethyl methyl ether, diisopropylethy-lamine, and catalytic DMAP in CH2CI2 afforded 75 in a 72% yield and was the first 1 derivative reported to have increased affinity at the KOP receptor relative to 1. [41, 52]. Based on the successful increase in affinity of derivative 75, additional simple alkoxymethyl ethers were obtained using appropriate alkyoxymethyl chloride with diisopropylethylamine in DMF (76-78). However, more complex alkoxymethyl derivatives were synthesized from the common methylthiomethyl ether intermediate (79), which was obtained from reaction of 57 with acetic acid, acetic anhydride, and dimethylsulfoxide (DMSO) [52]. Compound 79 was then... 

A few analogous derivatives with alkoxymethyl groups ((10) M = 2H, Cu, Zn, R = CH2OC7H15) were also prepared and showed mesophases, too. Two mesophases were observed for the free-base compound (Cr 79 Col 120 Colt > 300 dec.), while the Cu and Zn complexes showed only one as yet unidentified phase above 82 °C and 70 °C, respectively, until the materials decomposed above 300 °C. 

Introduction of alkoxymethyl groups to the phenyl ring of the 6, iV-chelating ligand leads to the formation of 481 and 482, and C6o-containing dinuclear complex 483. ... 

Hydroxymethyl complexes are often the most difficult members of the series to prepare and isolate. In some cases, such complexes can be s)mthesized through reaction of carbonyl complexes with NaEBHaCN) in alcoholic solutions. For example, the reduction of [M(CO)3(ri5-Cp)]+ (M = Ru, Fe) with a four-fold excess of Na[BH3CN] in methanol at 25 C produced the neutral hydrox)nnethyl complexes, [M(C0)2(CH20H)(Ti5-Cp)], in yields of 55% (Ru) and 45% (Fe).74 it has been shown S that [Fe(CO)2(CH20H)(ii5-Cp)]+ reacts further with Na[BH3CN] in methanol or ethanol to produce the alkoxymethyl derivative. Scheme 10.14 ... 

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