A-Undecane

Figure 3. TEM Micrographs (longitudinal view) of some samples synthesized using different alkanes as expanders, a undecane b dodecane.

Undecan-l-ol [112-42-5] M 172.3, m 16.5 . Purified by repeated fractional crystn from its melt or by distn in a vacuum. 

Bohlmann et al. (118-121) observed that an infrared absorption band between 2700-2800 cm is characteristic of a piperidine derivative possessing at least two axial carbon-hydrogen bonds in antiperiplanar position to the free-electron pair on the nitrogen atom. The possibility of forming an enamine by dehydrogenation can be determined by this test. Compounds which do not fulfill this condition cannot usually be dehydrogenated (50, 122,123). Thus, for example, yohimbine can be dehydrogenated by mercuric acetate,whereas reserpine or pseudoyohimbine do not react (124). The quinolizidine (125) enamines (Scheme 4), l-azabicyclo(4,3,0)-nonane, l-azabicyclo(5,3,0)decane, l-azabicyclo(5,4,0)undecane, and l-azabicyclo(5,5,0)dodecane have been prepared in this manner (112,126). 

Figure 15.11 (a) Total ion clnomatogram of a Grob test mixture obtained on an Rtx-1701 column, and (b) re-injection of the entire clnomatogram on to an Rtx-5 column. Peak identification is as follows a, 2,3-butanediol b, decane c, undecane d, 1-octanol e, nonanal f, 2,6-dimethylphenol g, 2-ethylhexanoic acid h, 2,6-dimethylaniline i, decanoic acid methyl ester ], dicyclohexylamine k, undecanoic acid, methyl ester 1, dodecanoic acid, methyl ester. Adapted from Journal of High Resolution Chromatography, 21, M. J. Tomlinson and C. L. Wilkins, Evaluation of a semi-automated multidimensional gas chromatography-infrared-mass specti ometry system for initant analysis , pp. 347-354, 1998, with permission from Wiley-VCH. 

In a 200-ml three-necked flask fitted with a dropping funnel (drying tube) is placed a solution of 13.4 g (0.12 mole) of 1-octene in 35 ml of THF. The flask is flushed with nitrogen and 3.7 ml of a 0.5 M solution of diborane (0.012 mole of hydride) in THF is added to carry out the hydroboration. (See Chapter 4, Section I regarding preparation of diborane in THF.) After 1 hour, 1.8 ml (0.1 mole) of water is added, followed by 4.4 g (0.06 mole) of methyl vinyl ketone, and the mixture is stirred for 1 hour at room temperature. The solvent is removed, and the residue is dissolved in ether, dried, and distilled. 2-Dodecanone has bp 119710 mm, 24571 atm. (The product contains 15 % of 5-methyl-2-undecane.) The reaction sequence can be applied successfully to a variety of olefins including cyclopentene, cyclohexene, and norbornene. 

Dibcnzyl-10-(2-propenyl)-9,ll-dioxa-3,6-dia7,a-10-borabic>clo[6.3.0 undecane-2,7-dione Typical Procedure33 ... 

The tartramide-based reagents, 10-allyl-3,6-dibenzyl-9,ll-dioxa-3,6-diaza-10-borabicyclo[6.3.0]-undecane-2,7-diones, are significantly more enantioselective than the parent tartrate ester derivatives7lb 73. Unfortunately, they have poor solubility at — 78 =C and consequently reactions times are long and conversions are often poor. The full scope of this tartramide reagent system awaits the development of a more soluble auxiliary. 

The synthesis of fUido-tricyclo[4.4.0.02 5]deca-3,8-dien-7,10-dione and verification of its endo-configuration has been reported earlier.3 This adduet is a useful starting material for the syntheses of tetracyclo-[5.3.0.02 6.03 10]deca-4,8-diene,s tricyclo[4.4.0.02 5]deca-3,7,9-triene,6 cis, syn, cjs-tricyclo[5.3.0.02,6]deca-4,8-dien-3,10-dione,7 and 4-oxahexa-cyclo[5.4.0.02 6.03 10.05 9.08,11]undecane.a... 

It is of interest to compare the relative intensities of all the alkyl ions formed from a singly branched paraffin with the intensities of the corresponding ions formed from normal paraffins. Table III lists the ratios of the relative intensities of the several alkyl ions formed from 2-methyldecane (compound 1, Table II) and normal undecane. Within the limits of accuracy and detail with which we are concerned, the intensities of all the ions except the Ci0H2i+ (m/e = 141) are the same. The low value of the ratio for m/e = 127 may be ascribed to a greater... 

Initial work was carried out with 3,9-bis(methylene-2,4,8,10-tetraoxaspiro[5,5] undecane) where R = H (11). However, this monomer contains two electron donor alkoxy groups on one double bond which is thus highly susceptible to a cationic polymerization. For this reason, the monomer is extremely difficult to handle and cannot be analyzed by gas chromatography since it does not survive passage through the column. It is prepared by the dehydrohalogen-ation reaction of the reaction product of pentaerythritol and chloro-acetaldehyde,... 

FIGURE 2 Glass transition temperature of a polymer prepared from 3,9- bis ( ethylidene- 2,4,8,10-tetraoxaspiro [ 5,5 ] undecane ) and mixtures of trans-cyclohexane dimethanol and 1,6-hexanediol as a function of mol% 1,6-hexanediol. (From Ref. 13.)... 

FIGURE 9 Effect of drug loading on cumulative drug release from polymer discs prepared from 3,9-bis(ethylidene-2,4,8,10-tetraoxaspiro-[5,5]undecane) and a 50 5Q mole ratio of trans-cyclohexane dimethanol and 1,6-hexanediol at pH 7.4 and 37 C. Drug loading 8 wt% (o),... 

FIGURE 18 In vivo cumulative weight loss (o) and cumulative release of levonorgestrel (o) from a crossUnked polymer prepared from a 3,9-bis(ethylidene-2,4,8,10-tetraoxaspiro[5,5]undecane)/3-methyl-1,5-pentanediol prepolymer crossUnked with 1,2,6-hexane triol. Polymer rods, 2.4 X 20 mm, containing 30 wt% levonorgestrel and 7.1 mol% Mg(OH)2. Devices implanted subcutaneously in rabbits. (From Ref. 15.)... 

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