Trimethylsilyl cellulose (TMSC) has been found to melt at 320–340°C in the absence of oxygen. When TMSC is prepared from chemical cellulose, using hexamethyldisilazane and a catalytic amount of chlorotrimethylsilane/pyridine in dimethylformamide, a thermoplastic material is obtained which may be melt spun into a fiber. This fiber, when treated with mild aqueous acid, yields regenerated cellulose plus hexamethyldisiloxane. The hexamethyldisiloxane can be converted back to hexamethyldisilazane by known chemistry. The fiber properties of the regenerated cellulose were found to be comparable to commercially available rayons. X‐Ray diffraction analyses of the cellulose suggest formation of an unusual polymorphic form.

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The 6-demethoxy analogue of thebaine has been easily prepared from codeine via isocodeine and its sulfenate ester. This diene, 7, readily undergoes reaction with vinyl ketones to afford Diels-Alder adducts of the 6,14-ethenomorphinan type. Further reactions afford the epimeric 19(R)- and 19(S)-butyl-6-demethoxy-7 alpha-orvinols (16). Pharmacological testing shows the R diastereomer to be highly analgesic and the s diastereomer to be a much less potent agonist, with similar potencies and relationships as found in the corresponding oripavine series. Thus, any hydrogen bonding between the 6-methoxyl group and the tertiary alcohol can be eliminated as contributory to either the activity of, or difference between the epimeric orvinols.

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6-[(£)-2-Butenylidene]-3-ethoxy-5,5-dimethyl-2-cyclohexen-l-one (3), 4-[(2?)-2-Butenylidene]-3,5,5-trimethyl-2cyclohexen-l-one (4), and 4-[(E)-l-(l-Ethoxy)ethoxy-2butenyl]-3,5,5-trimethyl-2-cyclohexen-l-one (5a). To a vigorously stirred solution of 2b (167 mg, 0.54 mmol) in hexane (9 mL) was added an ethereal solution of 1.5 M MeLi (0.7 mL, 1.05 mmol) at 3-4 °C. The mixture was stirred at 3-4 °C for 40 min, quenched with cold aqueous saturated NaHC03, and extracted with ether-benzene. The extracts were washed with aqueous saturated NaHCOa, dried (Na2S04), and concentrated. The residue was chromatographed (Si02, hexane-AcOEt 3:1) to give 21 mg (20%) of 42 (Rf 0.56, hexane-AcOEt 3:1), 8 mg (7%) of 32 (Rf 0.53), and 92 mg (61%) of 5a (Rf 0.48) as oils. 5a: bp 55.0-56.0 °C (0.007 mm, Kugelrohr); IR (neat) 3025,1665 (C=0),