The allyl group for protection in carbohydrate chemistry. Part 21. (±)-1,2 : 5.6- and (±)-1,2 : 3,4-di-O-isopropylidene-myo-inositol. The unusual behaviour of crystals of (±)-3,4-di-O-acetyl-1,2,5,6-tetra-O-benzyl-myo-inositol on heating and cooling: a ‘thermosalient solid’

Abstract

328ChemInform Abstract The racemic myo-inositol (Ia) is converted by a known procedure to a mixture of the bis-isopropylidene derivatives (Ib)-(Id) which are isolated as benzoates (IVa)-(IVc). In contrast to (IVb) and (IVc), a pure sample of (IVa) cannot be obtained and therefore a pure sample of its parent compound (Ib) is synthesized via the allyl ether (IVd). The allyl ethers (IVd)-(IVf) obtained from (Ib)-(Id) are separated and each is transformed to the respective di-O-allyl-myo-inositol (V). Kinetic acetonation of (Vb) gives the compound (VII). The desired pure (Ib) is then obtained from (IVd) (yield given in mg) by removing the allyl groups by isomerization and subsequent removal of the propen-1-yl groups formed using HgO/HgCl2. -Crystals of the diacetate (IX), obtained from (Vc) as outlined in the scheme (no yield given), show interesting 'jumping' behavior on heating and cooling.

Effect of Crystal Packing on the Thermosalient Effect of the Pincer‐Type Diester Naphthalene‐2,3‐diyl‐bis(4‐fluorobenzoate): A New Class II Thermosalient Solid

“…The meltw as cooled, and the solid material also movedw hile solidifying. [2][3][4][5][6][7][8][9][10][11] In contrastwith form I, crystals of form III did not show motion, as determined by HSM, and thus, this polymorph was determined not to be thermosalienta bove room temperature. Af ew crystals that did not jump melted at ah igher temperature ( Figure 1B).…”

“…Since its first observation, [1] the thermosalient effect-visually striking motion of crystals, whereby they are self-actuated and move rapidly owing to sudden release of strain-was and has remained as erendipitously observed phenomenon. [2][3][4][5][6][7][8][9][10][11][12][13] Early reports of this effect, which occursa saresult of am artensitictype structuralp hase transition, were without exceptiona result of carefulo bservation of crystals during measurement of their melting points, by which point some crystalsw eref ound to "jump"u pon heating in ac apillary or on ah ot stage.S ome of the modern sophisticated methods to determine the melting point or to record thermoanalytical curves by differential scanningc alorimetry (DSC) require crystals to be powdered and/or closed in the sample holder of the instrument. As in either case the sample is visually inaccessible, the thermosalient phenomenon mayh ave been overlooked because any changes in the appearance of the sample during heating could not be visually observed.…”

Unambiguous Total Synthesis of the Enantiomers of myo-Inositol 1,3,4-Trisphosphate: 1L-myo-Inositol 1,3,4-Trisphosphate Mobilizes Intracellular Ca2+ in Limulus Photoreceptors

“…28 Finally, the ketals were removed from 7 by heating in acetic acid-water (4:l) to give the tetrol S. 29 NMR data for compounds 5-8 have not been previously reported, and these are given in the Experimental Section.…”

Turning on Solid‐State Fluorescence with Light

“…This strong fluorescence turn-on is accompanied by vigorous blasting and/or jumping of the crystals in am anner that visually resembles the motility of thermosalient and photosalient solids. [16][17][18][19][20][21][22][23][24][25][26][27][28][29] Herein we report the reasons behind the dramatic enhancement of the emission of 3 and we explore the detailed mechanism of the related reaction.…”