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A powerful anion effect destabilizing alkali ion-crown complex formation has been found to operate in moderately concentrated protic (H2O, CH3OH, C2H5OH) solution, following the order HO- > AcO- > Cl- > Br- > NO3- > I- > NCS-. Evidence is provided that the observed effect does not originate from ion-pairing. A simple explanation is provided in terms of concordant hydrogen bond bridges of exalted stability between the gegenions, M+···OR-H···(OR-H)n···OR-H···A-. It is proposed that encapsulation of alkali ion by the macrocyclic ligand leads to a dissipation of the cation charge density destroying its ability to participate in the hydrogen bond bridge. An opposition against the alkali ion-crown complex formation arises accordingly in the solution in dependence on strength of the hydrogen bridge; for a given cation, the hydrogen bond strength increases with increasing anion charge density from NCS- to HO-(RO-). It is pointed out, at the same time, that the observed anion effect does not correlate with the known values of activity coefficients of the individual alkali salts which are almost insensitive to anion variation under the investigated conditions. As a resolution of the apparent paradoxon it is proposed that, in absence of the macrocyclic ligand, the stabilizing (concordant) bonding between the gegenions is nearly balanced by a destabilizing (discordant) hydrogen bonding between the ions of same charge (co-ions). Intrinsic differences among the individual salts are thus submerged in protic solvents and become apparent only when the concordant bonding is suppressed in the alkali ion-crown complex formation.

reaction of methylmagnesium iodide with 3-quinolinecarbonitrile gave a product of the 1,4-addition (IIa), whereas that of phenylmagnesium bromide gave products of the 1,2-addition (III) and the 1,4-addition (IIb). 6-Quinolinecarbonitrile (Va) exposed to the two agents gave ketones Vb and Vd, as well as products of the 1,2-addition and the subsequent oxidation (Vc and Ve); with phenyl magnesium bromide one more product was formed, viz. ketone Vf.

Complexing ability of the macrocyclic polyethers 18-crown-6, 15-crown-5 and 12-crown-4 has been investigated ebulliometrically in the homologous series of 0.6 molal ROM-ROH solutions (M = K, Na, Li; R = H, CH3, C2H5, n-C3H7, i-C3H7, t-C4H9). The values of complexation constants have been estimated in all the 54 crown-ROM combinations and the effects of cation, crown-cavity size and solvent have been examined. Two intriguing facts emerged from a comparison of the new results with the pertinent literature data. Firstly, it was found that the cation-crown cavity-complex stability variation in the ROM-ROH series disagrees with the well-known principle of steric match, the propensity of crowns to complexation decreasing in most instances in the order 15-crown-5 > 12-crown-4 > 18-crown-6 for the potassium and 12-crown-4 > 15-crown-5 > 18-crown-6 for the sodium alkoxide. An energetical preference of 2 : 1 over 1 : 1 crown-ROM complexes is presumably the responsible factor. Secondly, and even more importantly, it was found that complexation constants obtained in this study are strikingly small, the values for complexation of potassium and sodium alkoxides with 18-crown-6 being smaller by 3-7 power of ten than those which were previously obtained for the alkali ions, at lower concentrations. Evidence is provided that the difference does not originate from ion-pairing but from the operation of some effect which so far escaped notice.

Contrary to the widespread belief that counterion influences stability of charged complexes only in poorly solvating media, a dramatic effect of anion was discovered, ebulliometrically, in 0.6 molal M+X--C2H5OH (M = K, Na, Li; X = SCN, OC2H5) and in 0.6 molal M+X--H2O (M = K; X = SCN, OH) solution upon complexing with 18-crown-6,15-crown-5 and 12-crown-4. Out of the nine crown-MSCN combinations examined in the ethanolic solution, seven yielded 1 : 1 (18-crown-6-KSCN, 18-crown-6-NaSCN, 15-crown-5-NaSCN, 15-crown-5-LiSCN, 12-crown-4-KSCN) or 2 : 1 (15-crown-5-KSCN, 12-crown-4-NaSCN) complexes quantitatively, whereas the corresponding crown-MOC2H5 combinations did not complex at all or the complexation was very incomplete. An analogous situation was found in the aqueous solution, with KSCN complexing 18-crown-6 quantitatively or 15-crown-5 and 12-crown-4 partly, whereas KOH did not yield complexes with any of the three crowns. Evidence is presented that the observed effect of anion does not originate from ion-pairing.

The reduction of 2-, 3- and 4-acetylquinolines (Ia-c) by triethylammonium formate affects both the pyridine part of the quinoline nucleus and the carbonyl groups, giving rise to products II-VI.

Phase transfer catalysis allows a synthesis of oligoethylene glycol di-p-toluenesulphonates IVa-e and V from the corresponding diols Ia-e and II, respectively, in yields ##a 95%. A preferential tosylation of primary hydroxyl groups in the diols IIIa and IIIbcan be also accomplished almost quantitatively under the phase-transfer conditions.

The title effect has been investigated in the homologous series of erythro- and threo-5,6-dihalodecanes (X = Br, Y = I; X = Cl, Y = I; X = F, Y = I; X = Br, Y = Br; X = Cl, Y = Br; X = F, Y = Br; X = Cl, Y = Cl; X = F, Y = Cl). It has been found that proportion of syn-elimination in the overall reaction varies with the variation of the halogen leaving groups in the order I < Br < Cl < F, ranging between the extreme 3-30% in the erythro- and 5-60% in the threo-series. On basis of the variable transition state theory, observed pattern of syn-anti dichotomy has been correlated with the extent of double bond development in the transition state.

Whereas 2-quinolinecarbonitrile (Ia) is not reduced with triethylammonium formate, 3-quinolinecarbonitrile (Ib) affords a mixture of 1,4-dihydro-3-quinolinecarbonitrile (IVb) and 1-formyl-1,2,3,4-tetrahydroquinoline-3-carboxamide (IIa) in addition to the corresponding acid IIb. 4-Quinolinecarbonitrile (Ic) is reduced to 1-formyl-1,2,3,4-tetrahydroquinoline-4-carbonitrile (IId) and 1-formyl-1,2,3,4-tetrahydroquinoline (IIc). Reduction of 3-quinolinecarbonitrile methyl methosulfate (Va) at low temperature leads to 1-methyl-1,4-dihydroquinoline-3-carbonitrile (IVc) whereas at higher temperatures it affords, in addition to IVc, 1-methyl-1,2,3,4-tetrahydroquinoline-3-carboxamide (IIf) and the acid IIg. 4-Quinolinecarbonitrile methyl methosulfate (Vb) gives 1-methyl-1,2,3,4-tetrahydroquinoline-4-carbonitrile (IIh) and 1-methyl-1,2,3,4-tetrahydroquinoline (IIe).

Reduction of the compounds mentioned in the title with triethylammonium formate gave 1-formyl-C-methyl-1,2,3,4-tetrahydroquinolines IIa-IIc. On reduction of derivatives substituted in the position 3 and 4 (Ib, Ic, Ie, If, Ih, Ii) the products of 1,2-addition are also formed i.e. IIIa, IIIb, and on reduction of 3-quinolylmethanol (Ie) and 3-quinolinecarboxaldehyde (Ih) the products of 1,4-addition, i.e. IVa, IVb also result. Alcohol If and aldehyde Ii also give the product of the reduction of the functional groups, i.e. 4-methylquinoline (Ic). When 3-quinolylmethanol (Ie) was prepared by reduction of aldehyde Ih with sodium borohydride 1,2,3,4-tetrahydro-3-quinolylmethanol (IIe) was also isolated.

Reduction of 3-substituted quinoline derivatives, containing electron donating substituents (Ia-Id), as well as of the quaternary salts VIb and VIc, with triethylammonium formate afforded mainly the corresponding 1-formyl-1,2,3,4-tetrahydroquinolines II or their 1-methyl derivatives. Analogous reductions of quinoline derivatives, containing electron withdrawing groups (e.g. Im) gave 1,4-dihydroquinolines IV in addition to 1,2,3,4-tetrahydroquinoline derivatives. Quaternary salts of 3-substituted derivatives with electron withdrawing substituents (e.g. VId) were reduced exclusively to 1-alkyl-1,4-dihydroquinolines IV.

The title problem has been investigated polarographically in the homologous series of erythro and threo-5,6-dihalodecanes (X = Br, Y = I; X == Cl, Y = I; X = F, Y = I; X = Br, Y = Br; X = Cl, Y = Br; X = F, Y = Br; X = Cl, Y = Cl; X = F, Y = Cl). Each dihalide from the series gave a single two-electron wave. A very pronounced dependence of half-wave potential on halogen group identity was found in the series, the E1/2 values ranging from -0.3 V (X = Br, Y = I) to -2.8 V (X = F, Y = Cl). Controlled-potential electrolyses of the dihalides were accomplished at mercury pool electrode affording always cis- and/or trans-5-decene as the sole product, in almost quantitative (>90%) yields. Stereochemistry of the dehalogenation was deduced from the olefin-isomer distribution data determined by VPC. Very marked differences were found in the series, the elimination stereochemistry ranging between a clean anti and a prevalent syn, in dependence on the identity and configuration of the halogen groups.

Association degrees have been determined in 0.03-0.8 molal t-C4H9OLi-t-C4H9OH, t-C4H9ONa-t-C4H9OH and t-C4H9OK-t-C4H9OH solutions in the absence and also in the presence of three different crowns (18-crown-6, 15-crown-5 and 12-crown-4). It has been found that presence of any of the three crowns does not affect association degree in the alkoxide solutions. t-C4H9OLi is on average dimeric in 0.03 molal and tetrameric in 0.4-0.8 molal solution, whereas t-C4H9ONa and t-C4H9OK are in the full concentration range monomeric ion pairs, in the absence as well as in the presence of the crowns. Of the nine tert-butoxide-crown combinations studied, only two, t-C4H9OK-18-crown-6 and t-C4H9OK-15-crown-5, yielded complexes quantitatively, in the form of 1 : 1 complexed ion pairs. An incomplete complex formation (10-30%) has been observed with the combinations t-C4H9OK-12-crown-4, t-C4H9ONa-18-crown-6, t-C4H9ONa-15-crown-5, t-C4H9ONa-12-crown-4. No complex formation has been detected with t-C4H9OLi, in combination with any of the three crowns. Complex stability decreases in the order K(+) > Na(+) > Li(+), regardless of the crown cavity size. At variance with the prevailing opinion it indicates that steric fit between cation and crown is not the main factor which controls complex stability in the solution. A cooperative influence of anion on crown complex stability is considered in terms of the theory of hard and soft acids and bases.

Degrees of ionic association, napp, were ebulliometrically determined in 0.06-0.6 molal region for eighteen RO(-)M(+)-ROH base-conjugate acid combinations (R = H, CH3, C2H5, n-C3H7, i-C3H7, t-C4H9; M(+) = Li(+), Na(+), K(+)) and found to range between the extremes 0.5 and 0.4. Presence of ion-pair aggregates (napp > 1) was established only in two of the examined combinations (i-C3H7OLi-i-C3H7OH and t-C4H9OLi-t-C4H9OH).

A synthesis of twelve heteroanalogues II-XIII of the plant growth stimulator 1-triacontanol (I), derived from the parent alcohol by a replacement of 1-4 methylene units by heteroatoms O, S, NH and/or by a replacement of 1-2 ethylene units by -CO-O-, -CO-NH- or epoxy groups is reported. Spectral and gas-chromatographic properties (Kováts retention indices) of the compounds are described.

A simple regio- and stereoselective synthesis of unsaturated analogues of the plant growth stimulator 1-triacontanol from ω-alkyn-1-ols is reported. Starting from the easily accessible 10-undecyn-1-ol, eight n-C30 alcohols containing -C ≡ C-, (E) -C=C- or (Z) -C=C- group in the position 21 and/or 10 have been prepared. Spectral and gas-chromatographic properties (Kováts retention indices) of the novel compounds are described.