Hydrogen dichloride

Reactions of enamines with aluminum hydrogen dichloride (540,541) (UAIH4 and AICI3) or aluminum hydrogen dialkyl compounds (542) led to organoaluminum intermediates which could be hydrolyzed to tertiary amines or oxidized to aminoalcohols. The formation of olefins by elimination of the tertiary amine group has also been noted in these reactions. 

The stereochemical course of reduction of imonium salts by Grignard reagents was found to depend on the structure of the reagent 714). Hydro-boration of enamines and oxidation with hydrogen peroxide led to amino-alcohols (7/5). While aluminum hydrogen dichloride reacted with enamines to yield mostly saturated amines and some olefins on hydrolysis, aluminum hydride gave predominantly the unsaturated products 716). 

At low temperatures partial reduction of chlorine occurs, forming yellow unstable chloro derivatives, arsenic dihydrogen chloride and arsenic hydrogen dichloride ... 

Bis(2,4-pentanedionato) boron(III) hexachloroantimonate(V) crystallizes from chloroform-ether as long, flat, cream-colored needles which melt with decomposition at 155-157°C. Its solubility properties are similar to those of the hydrogen dichloride salt. In deuteriochloroform solution (concentration, 10 g./lOO ml. of solvent) the compound exhibits proton ri.m.r. lines at r = 3.44 (ring protons) and r = 7.45 (methyl protons). 

In the case of 1-phenylpropyne a vinyl cation is suggested as intermediate. The kinetic law is rate = k3 [—C=C—] [HC1]2. The second order dependence on HC1 is explained by assuming that proton transfer to the triple bond results in the anion hydrogen dichloride, HClJ. The product distribution and the stereochemistry, under kinetic control, have been explained by assuming that a cw-oriented intimate ion-pair, 14 is initially formed which, following Scheme 2, may either collapse to cis chloride, undergo anion displacement by acetic acid to form tram acetate or a randomly oriented (solvent separated) ion-pair 15 which gives racemic material. 

Pocker also reported that hydrogen chloride can induce the ionisation of aralkyl chlorides in media where the hydrogen dichloride anion is a relatively stable entity, i.e., nitromethane nitrobenzene and benzene Such situations would therefore be expected to give olefin polymerisation in the presence of Lewis acids, owing to the higher lifetime of the carbocations formed as intermediate, but as we shall see this is not always observed experimentally. 

If, as in the preceding scheme, the hydrogen dichloride anion is the relevant species, the equilibrium concentration of (paired) carbenium ions formed will be governed by the same equation, and the rate of polymerisation will also follow the same kinetic laws, assuming that protonation is rate determining. 

Reaction of 2-substituted-1,3-dithianes with sulfuryl chloride in strictly anhydrous conditions gives 1,3-dithienium hydrogen dichlorides, which are extremely hygroscopic and hydrolysable <83CB1739>. Chlorination of 1,3-dithianes at the C-2 position occurs with common sources of electrophilic chlorine such as sulfuryl chloride or NCS, presumably through initial chlorination at sulfur and Pummerer-type rearrangement (Scheme 25a) <94JOCl672>. 

Sodium and lithium Both sodium [15] and lithium [16] electrodeposition was successful in neutral chloroaluminate ionic liquids that contained protons. These elements are interesting for Na- or Li-based secondary batteries, where the metals would serve directly as the anode material. The electrodeposition is not possible in basic or acidic chloroaluminates, only proton-rich NaQ or LiQ buffered neutral chloroaluminate liquids were feasible. The protons enlarged the electrochemical window towards the cathodic regime so that the alkali metal electrodeposition became possible. For Na the proton source was dissolved HQ that was introduced via the gas phase or via 1-ethyl-3-methylimidazolium hydrogen dichloride. Triethanolamine hydrogen dichloride was employed as the proton source for Li electrodeposition. For both alkali metals, reversible deposition and stripping were reported on tungsten and stainless steel substrates, respectively. 

The proton NMR of the hydrogen dichloride ion has been studied in chloroform solution, and a limiting t value of -2,7 observed, relative to tetramethyl silane as 10,0. A similar value has been obtained in nitromethane solution. The concenuation dependence of the shift, in chloroform, is shown in fig. 2. The chemical shift for the dichloride ion is fat to low field of the values for hydrogen chloride in chloroform, and for liquid hydrogen chloride. We therefore conclude that the shielding of the proton is much reduced in the dichloride ion. 

C22H30CI2O7, Tri-p-methoxyphenylmethyl hydrogen dichloride tetrahyd-rate, 30B, 55... 

Chloride hydrochloride [21006-73-5]. Tetraphenylarsonium hydrogen dichloride, 9CI Needles -H 2H2O (dil. HCl). Mp 205-209° dec. 

Tetraphenylantimony bromide, see B-00577 >Tetraphenylarsonium(l -I-), T-OOl 19 Tetraphenylarsonium hydrogen dichloride, in T-OOl19... 

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