Ether Route

The nonhydrolytic ether route involving the reaction of metal chloride precursors with diisopropyl ether was developed for the synthesis of mesoporous mixed 

The nonhydrolytic M—O—M bond formation via ester elimination between metal alkoxides and carboxylic acids is a well-known approach in sol-gel chemistry. In this direction, titanium -butoxide and acetic acid were used for the nonhydrolytic synthesis of anatase Ti02 nanopartides at 100 °C [92]. Moreover, spindle-shaped nanoporous anatase Ti02 mesocrystals with a single-crystal-like structure and tunable sizes were synthesized in the tetrabutyl titanate and acetic acid system without any additives imder solvothermal conditions [93]. A complex mesoscale assembly process, involving oriented aggregation of tiny anatase nanocrystals and entrapment of in situ produced butyl acetate as a porogen, was proposed for the formation of the mesocrystals. They exhibited a good performance as anode material for lithium ion batteries [93]. 

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Racemic and chiral syntheses of some indolo[2,3-<2]quinolizidine alkaloids through a lactim ether route 98H(47)525. 

Yu, Q.S. Lu, B.Y (1994) Total Synthesis of Racemic Physostigmine, Physovenine and its Sulfur Analog by the Oxindole-5-O-tetrahydropyranyl Ether Route. Heterocycles, 39, 519-525. 

Composition. Crystals deposited from ethanol solution as well-formed thin plates. The fatty acid content of the crystals is given in Table I. For all chain lengths the acid content approximates closely that required for 1 to 1 stoichiometry. This is also the case for most of the acid-soaps prepared by the petroleum ether route the low values of titratable acid in some instances are ascribable to the presence of free soap. 

The composition data obtained for the series of mixed fatty acid-potassium soap systems, prepared by both the ethanol and petroleum ether routes, lend strong support to the formation of 1 to 1 acid-soap complexes. It is of interest to inquire into the phase relationships in these two-component systems. A phase diagram presented by McBain and Field (15) for the lauric acid-potassium laurate system shows that compound formation takes place between the two components at the 1 to 1 molar ratio, but the compound undergoes melting with decomposition at 91.3 °C. [A similar type of phase behavior has been reported by us for the sodium alkyl sulfate-alkyl alcohol (9) and sodium alkyl sulfonate-alkyl alcohol (12) systems, but in these cases the stoichiometry is 2 to 1]. 

The scope and synthetic utility of dioxyphosphoranes, and particularly, diethoxytriphenylphosphorane (DTPP), as useful cy-clodehydrating "reagents" for the conversion of diols to cyclic ethers have received only superficial attention (1). The DTPP-diol - ether route has several unique advantages over existing methods (a) the reaction conditions are effectively neutral and mild, (b) the stereoselectivity in the closure of both unsymmet-rical and symmetrical diols to cyclic ethers is high, and (c) the isolation of the product(s) from triphenylphosphine oxide (TPPO) is convenient. 

Torek, B., Convers, A., Cbauvd, A, "MeAaool for motor bud via the ethers route, Chan. Engng Progress, 78 (8) 36-45 (1982). 

The enol ester or silyl enol ether route to enolates has advantages over direct deprotonation in certain cases. If direct deprotonation provides a mixture of regio- or stereo-isomers, it is often possible to trap the enolate mixture by esterification or silylation, separate the desired enol ester or silyl enol ether and regenerate the enolate by reaction with methyllithium. It is also useful for preparation of enolates from substances that are so electrophilic that direct deprotonation is complicated by self-aldolization. For example, aldehyde enolates have been prepared in this manner (equation 14). ... 

By ether route, the alkoxide is formed in situ along with alkyl halide ... 

Surprisingly, the yield of the synthesis was 95.5%, which is higher than the etherate route for fosfotungstic acid (see Section 5.2.1). 

The synthesis displays interesting stereochemical features. Thus, ethyl 2-(l -benzyloxycarbonylaminoethyl)-(J )-2-thiazoline-4-carboxylate (197) was obtained (0 by the imino-ether route , by condensing L-2-benzyloxy-carbonylaminopropioimino ethyl ether (198) and ethyl L-cysteinate hydrochloride (route A) and (ii) by the dehydration of benzyloxycarbonyl-L-alanyl-L-cysteine ethyl ester (199) (route B). Acidic hydrolysis of the... 

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