Boron chloride compound with

BBrj Boron bromide, 3 27, 29 BCls Boron chloride, 3 27, 28, 29 BCls CCHslsN Boron chloride-trimethylamine, 6 27 BCI3-PCI5 Boron chloride, compound with phosphorus (V) chloride, 7 79... 

The synthesis of the representative compound of this series, 1,4-dihydro-l-ethyl-6-fluoro (or 6-H)-4-oxo-7-(piperazin-l-yl)thieno[2/,3/ 4,5]thieno[3,2-b]pyridine-3-carboxylic acid (81), follows the same procedure as that utilized for compound 76. Namely, the 3-thienylacrylic acid (77) reacts with thionyl chloride to form the thieno Sjthiophene -carboxyl chloride (78). Reaction of this compound with monomethyl malonate and n-butyllithium gives rise to the acetoacetate derivative (79). Transformation of compound 79 to the thieno[2 3f 4,5]thieno[3,2-b]pyhdone-3-carboxy ic acid derivative (80) proceeds in three steps in the same manner as that shown for compound 75 in Scheme 15. Complexation of compound 75 with boron trifluoride etherate, followed by reaction with piperazine and decomplexation, results in the formation of the target compound (81), as shown in Scheme 16. The 6-desfluoro derivative of 81 does not show antibacterial activity in vitro. 

The gas phase polymerization of diisobutylene with boron fluoride also did not occur unless a third component was present. The addition of water or acetone caused the mixture to react rapidly, the boron fluoride combining instantaneously with the vapor of the third component in approximately equimolecular quantities. Certain substances, oxygen, hydrogen sulfide, and hydrogen chloride, did not produce a rapid polymerization of diisobutylene these substances did not combine with the boron fluoride. In each of these cases, the final addition of water to the nonreacting mixture resulted in rapid polymerization. Ammonia formed an addition compound with the boron fluoride in approximately equimolecular quantities, but did not bring about the polymerization of the diisobutylene until water vapor was added, after which rapid reaction occurred (Evans and Weinberger, 85). 

Wittig and co-workers2 have shown that triphenylborane can be readily synthesized in high yield by simple thermal decomposition of trimethylammonium tetraphenylborate. They obtained the latter compound by collecting the precipitate which was formed on mixing aqueous solutions of trimethylammonium chloride and lithium tetraphenylborate. The lithium salt was isolated from the products of the reaction of boron trifluoride-etherate with... 

Trimetaphosphimic acid, 6 79 Trimethylamine, coordination compounds with boron fluoride and chloride, 5 26, 27 purification of, 2 159 Trimethylamine-sulfur dioxide, 2 159... 

The SjSii ring system is susceptible to attack by nucleophiles, as is illustrated for 636. Examples of nucleophiles are alcohols (best with primary and secondary), 1563-1538 phenols,hydroxide ion, water, " and carboxylic acids. The boron compound 641 reacts with 636 to give the five-membered heterocycle 642. The electrophilic reagents, acetyl chloride and benzoyl chloride, react with tetraphenylcyclodisiladithianes to give the diacyl sulfide and dichlorophenyl-silane. ... 

The boron trihalide complexes with a number of phosphine sulphides and selenides can be isolated for the chloride, bromide, or iodide but, consistent with its reduced Lewis acidity, the trifluoride does not react.600 Alkyldithio-phosphonic acids give tin, lead, and mercury derivatives such as Me3SnSP-(S)FEt, Pb[SP(S)FMe]2, and MeHgSP(S)FMe, which are monomeric in solution, and there is n.m.r. evidence for a bidentate phosphonate group in the tin compound.601 Vanadyl chelates of alkoxy-ethyl and alkoxy-phenyldi-thiophosphonates (87) have been synthesized and e.s.r. measurements... 

Whereas the addition compounds of boron trichloride with dimethyl ether and with diethyl ether are stable at room temperature, BCls eflfects cleavage of tetrahydro-furane, and it reacts with ethyleneglycol dimethyl ether even at 0° with evolution of methyl chloride, presumably with formation of the mono- and dichloroboronates ... 

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