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Oxacycle ring-opening reactions from a non-HCFC-based source of phosphonodifluoromethyl carbanion 1 are reported. This straightforward strategy opens access to a variety of primary and secondary ω-hydroxy-α,α-difluoromethylphosphonates via one step. The syntheses of a glycerol monophosphate analogue and precursors to nucleoside phosphorylase inhibitors are described using this method.

The Provox® (Atos Medical AB, Hörby, Sweden) voice prosthesis was developed between 1988 and 1990 and has been used at our centre with regular success since 1993. Since 1996, a second generation of Provox® (Provox®2) has been used, which can be inserted by an anterograde technique. The aim of this study is to compare the survival lifetime of both voice prostheses. The survival time of the two voice prostheses were compared retrospectively in 152 devices placed in 38 patients. A Kaplan-Meier analysis was performed to determine the survival lifetimes and a log rank test was performed to compare the two curves. Clinical factors affecting the lifetime were also analysed with a Kaplan-Meier plot.The median survival lifetime of the Provox® and Provox®2 were 303 and 144 days respectively. The Kaplan-Meier estimation shows that this difference is statistically significant (p=0.02). It is considered an early failure if it occurs within the first three months. There was a larger number of early failures with the Provox®2 than with the Provox® (p=0.04). Neither the gender nor the age affected the lifetime of the devices. Radiotherapy seemed to lengthen the lifetime of the first valve.The survival lifetime of the second generation Provox®2 valve is shorter than the lifetime of the first generation Provox®. This could be due to the difference in elasticity of these valves that could lead to a different level of colonization and invasion of the valves by micro-organisms.

A two-step, high-yielding synthesis of Δ²-thiazolines containing a difluoromethylphosphonate diester moiety has been devised using a building block approach. Racemic or chiral β-amino alcohols and diols were coupled with methyl difluoro(diethoxyphosphono)dithioacetate to give predominantly the corresponding β-hydroxythioamides, which were then cyclized to provide a series of novel substituted Δ²-thiazolines.

Two different strategies are shown to produce sulfanyl and selanyldifluoromethylphosphonates. Thus, treatment of sulfanyldichloromethylphosphonates by 3HF·NEt3 in the presence of zinc bromide produces the corresponding sulfanyldifluoromethylphosphonates. In addition, lithiation of difluoromethylphosphonates followed by quenching with phenylsulfanyl chloride, phenylselanyl chloride, or diphenyl diselenide yields the corresponding sulfanyl- and selanyldifluorophosphonates. Generation of phosphonodifluoromethyl radicals from such precursors in the presence of alkenes produces the expected adducts.

Since the first reliable mediastinal tracheostomy described by Grillo et al. in 1966, many new techniques have been described in order to reduce the number of complications. We here report the case of a 55-year-old man who was referred for surgery with post-radiochemotherapy recurrence of a double neoplasm of the pharyngolarynx extending to the proximal trachea and the medial part of the oesophagus. Through a median sternotomy, a pharyngolaryngoesophagectomy was performed with an extended tracheal resection. The reconstruction of the upper digestive tract was performed with a gastric pull-up. The mediastinal tracheostomy was performed with a pectoralis major muscular flap through a right unilateral resection of the manubrium, the right clavicular head and the right first and second costal cartilages. Historically, the mediastinal tracheostomy was performed through a large bilateral resection of the anterior chest wall, in order to prevent the tension on the tracheocutaneous sutures. Nowadays, with the possibility of various pedicled flaps, bilateral resection no longer seems to be necessary. This unilateral resection leads to a reduction in post-operative sequelae.

Stereoselective syntheses of (Z)-fluoroalkenoates 3a−g have been developed in three steps from the readily available fluorosulfide 5 and aldehydes. This preparation, involving a Durst reaction, was highly stereoselective and led to fluoroalkenes in 50−60% overall yields, without purification of intermediates.

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