Dilithium sulfide

Digermyl sulfide (digermathiane) has been prepared by the reaction of iodoger-mane with mercury(II) sulfide and, more recently, from bromogermane and dilithium sulfide in dimethyl ether. (Methylthio)germane has been prepared by... 

Dilithium sulfide is first prepared. Ammonia (ca. 10 ml.) is condensed onto lithium (39 mg., 5.6 mmoles) and sulfur (93 mg., 2.9... 

Dilithium carbonate. See Lithium carbonate Dilithium monosulfide. Sto Lithium sulfide Dilithium oxide. See Lithium oxide Dilithium sulfide. See Lithium sulfide Dill. See Dill (Anethum graveolens)... 

CAS 12136-58-2 EINECS/ELINCS 235-228-1 Synonyms Dilithium monosulfide Dilithium sulfide... 

Another method for e preparation of aryl w-dimethoxyethyl sulfides was described by Pandya and Tilak. The procedure consists in allowing aryl lithium derivatives to react with 2,2,2, 2 -tetramethoxy-diethyl disulfide. Subsequent cyclization of the sulfides by polyphos-phoric acid yields 2-35% of condensed thiophenes and thiopyrans. By this method, thienothiophene 1 was prepared from 2-thienyllithium [Eq. (12)] and the previously unknown dithieno[2,3-6 3, 2 -i/]thiophene (5) was obtained from thienyl-2,5-dilithium. The possibility of synthesizing a heterocyclic analog (25) of pentacene from dithieno[2,3-6 3 2 -[Pg.130]

A 94% yield of 3,4 -dibromo-2,3 -dithienyl sulfide (184) was similarly achieved from 3-bromo-2-thienyllithium (180) and disulfide 182. Oxidative ring closure of the dilithium derivative of 184 gave dithienothiophene 8 in 29% yield [Eq. (53)]. 

The additions of disodium telluride, dilithium telluride and disodium selenide to chloromethyl alkynyl sulfides and tellurides give a variety of 1,3-dichalcogenoles as shown in Scheme 15 (81RTC10,82TL1531>. The preparation of the 1,3-ditelluroles required the use of dilithium telluride under carefully controlled conditions. 

The phenyl sulfides available permit the synthesis of organolithium by reaction (c) (see Table 2), e.g., tertiary alkyllithiums that are not available from the corresponding halides and sulfur-stabilized vinyllithiums that serve synthetically as acyl anion equivalents. Also, the benzyl ether moiety is not cleaved when the substrate contains both this moiety and a thiophenol group, and bis(phenyl sulfides) may be treated with 1-2 equiv of Li metal to give the mono- or dilithiums, respectively. 

Coupling. Dilithium tetrachloi bromide with a,cti-dibromoalkanes have also been used as coupling par Ss2 displacements. The open lions of chlorides are regio- and sten alized allyl thiazolin-2-yI sulfides ii... 

Carbopalladation. Allylic amines and sulfides form palladium complexes in high yield with dilithium tetrachloropalladate (THF, 20°, 6-8 hours). These complexes react with certain carbanions at the jS-position, a site that is not susceptible to nucleophilic displacement in allylic amines and sulfides. The complexes need not be isolated these reactions are conducted in THF at room temperature by reaction of the allylic amine or sulfide with the carbanion in the presence of 1 equiv. of LizPdCU (equations I and II). The products are the palladium complexes 1 and 3. These are reduced by sodium borohydride or sodium cyanoborohydride... 

Dilithium tetrachlorocuprate is recommended as an additive for cross coupling of Grignard compounds with tosylates even allylic and benzylic acetates give good yields . a-Methylene-ketones, -carboxylic acids and -lactones have been prepared via sulfides and sulfoxides. A convenient and general synthesis of acetylene derivatives from boranes via the reaction of iodine with lithium 1-alkynyltriorganoborates has been published ar-Nitrostyrenes can be easily obtained by a Wittig synthesis with formaldehyde in an aqueous medium . A new synthesis of unsym. ketones by reaction of dialkyldiloroboranes with lithium aldimines has recently been published . Metallo aldimines have also served for the synthesis of a variety of other compound classes such as a-hydroxyketones, a-keto acids, nitriles, and for the asym. synthesis of a-amino acids . Polycondensations of malononitriles with benzylic chlorides have been carried out quantitatively under mild conditions in dimethyl sulfoxide with triethylamine as acid acceptor . Carbonyl compounds can react with dibromoacetonitrile to yield a-bromo esters with additional carbon atom . ... 

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