Optical heating

Heating optically active (5)-3-bromo-3-methylhexane with aqueous acetone results in the formation of racemic 3-methyl-3-hexanol. 

Turbine Package Electrical Fire Hydrocarbon Fire Heat Optical NFPA 30, Section 5-5.5.1. 

The synthesis of camphor (80% optical purity) by heating optically pure di-hydrocarvone at 400 °C for 20 h is reminiscent of Money s racemic camphor synthesis (Vol. 1, p. 39) in that both correspond to a biogenetic-type synthesis via enol formation. Further synthetic work on deuteriated camphors (see references therein and Vol. 3, p. 67 Vol. 4, p. 48 Vol. 7, p. 38 for earlier work) includes syntheses of optically pure [8- Hi]-, [8- H2]-, and [8- H3]-(—)-camphor (204) by modification of known reactions (Scheme 5) and the use of an improved Zn-Cu... 

Upon heating optically active 49-1-d at 230°C (67) deuterium scrambling isomerization 49-1 -d - 49-5-d and racemization (+)-49 - (-)-49 were observed to take place at approximately the same rate. A reasonable explanation of this result is a degenerate walk rearrangement with inversion at C-7. 

Examples of this type of reaction are Sjyfl reactions in which the leaving group departs from a chirality center. These reacdiions almost always result in extensive and sometimes complete racemization. For example, heating optically active (5)-3-bromo-3-methylhexane... 

The optical apertures used in near-field microscopy are usually prepared by pulling a heated optical fibre until it breaks [25]. The sides of the tips are coated with aluminum. The typical diameters of the apertures produced by this technique are 60 10 nm, which is about one tenth of the optical wavelength. The transmission of such a tip ranges from 10 to 10 . The near-field tip is mounted on a xyz-piezo-electric (PZT) tube scanner to control the fine approach (2) to the surface and the lateral dithering (x,y) of the tip. The coarse z positioning was achieved by a coupled spring and steel plate comparable to the setup described in [30]. The sample was connected to a small glass hemisphere to minimize losses due to internal reflections and mounted in the focus of a paraboloid mirror with a numerical aperture of NA = 0.98. The whole setup, paraboloid mirror, sample, and PZT tube with the fibre tip, was then mounted inside a cryostat and immersed in superfluid Helium at 1.8 K. 

Heating optically active 47/-pyrido[l,2-a]pyrimidin-4-one 276, prepared from 2-chloro-3-formyl-477-pyrido[l,2-a]pyrimidin-4-one and (2 5,3 )-ethyl 4-(2-pyrrolidinyl)-but-3-enoate in THF in the presence of NEts gave single isomer 277. Reaction of 276 with (R)-l-phenylethylamine (271) in the presence of MS (4 A) gave also a single isomer 278, which converted to compound 279 on silica gel, or in a solution of CDCI3. Reaction of 4//-pyrido[l,2-a]-pyrimidin-4-one 276 and 271 in boiling benzene yielded also... 

Tank or Vessel Storage Hydrocarbon Fire MPS Heat Optical NFPA 30... 

OfBhore Drilling or Production Facility Hydrocarbon Fire Electrical Fire MPS Smoke Heat Optical NFPA30 API 14 C... 

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